1. Compare and contrast the characteristics of metals and nonmetals.
2. Describe the electrochemical series and why it’s important in understanding metals.
3. Describe the theory of ionization in regard to acids and bases.
4. Identify the role of indicators.
Answers
Answer:
1. Both metals and nonmetals are types of elements and can be involved in chemical reactions. Some of their differences are highlighted in the chart below.
Metals:
Appearance; Shiny.
Conduct heat or electricity; Yes.
Malleable or ductile; Yes, both and has great mechanical strength.
Form stable compounds; Forms stable compounds with acids; also forms oxides; replaces hydrogen in acids or water; combine with nonmetals; often becomes positive.
Nonmetals :
Appearance; Not shiny .
Conduct heat or electricity; Not well .
Malleable or ductile; Brittle and not easily molded into shapes .
Form stable compounds; Oxides usually give acid reactions in water; often becomes negative
2. The electrochemical series is an arrangement of metals in such order that any metal in the list is displaced from its compounds by any metal above it, but displaces any metal below it. The higher up the list a metal is, the greater its activity. Knowing a metal’s placement on this chart can help you understand the activity of the metal, especially in regard to its ability to displace hydrogen in acids. Any items on the list far above hydrogen will do a good job at displacing it, those near it won’t do such a good job, and those below it won’t displace it from acids at all.
3. When placed in water, acids dissociate and form free hydrogen ions, which determine the properties of acids. The number of hydrogen ions determines the strength of an acid. Strong acids dissociate to a large degree and produce a large number of hydrogen ions. Weak acids dissociate to only a slight degree.
When placed in water, bases dissociate and form free hydroxyl ions, which determine the properties of bases. Strong bases dissociate to a great degree and produce a large number of hydroxyl ions. Weak bases dissociate to only a slight degree.
When free hydrogen ions and free hydroxyl ions are removed from solutions of acids and bases, then the acidic and basic properties disappear. This is what happens when acids and bases are mixed together in proper proportion; the hydroxyl ion will unite with the hydrogen ion to form water. The resulting salt product is neutral.
4. Indicators are used to help determine the pH value of an unknown solution. These are often papers that turn a certain color at certain pH values.
Metals are good conductors of heat and electricity but the non-metals are not.
Compare metals and non-metalsMetals are good conductors of electricity and heat whereas non-metals are poor conductors of heat and electricity. Metals have high density while on the other hand, non-metals have low density. Metals are malleable and ductile whereas non-metals are brittle.
So we can conclude that metals are good conductors of heat and electricity but the non-metals are not.
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Related Questions
A car with a mass of 700 kg is moving with a speed of 20m/s.
Calculate the kinetic energy of the car.
Answers
Answer:
The answer is 140,000 JExplanation:
The kinetic energy of an object can be found by using the formula
\(KE = \frac{1}{2} m {v}^{2} \\ \)
where
m is the mass
v is the velocity
From the question we have
\(KE = \frac{1}{2} \times 700 \times {20}^{2} \\ = 350 \times 400\)
We have the final answer as
140,000 JHope this helps you
Which elements had only one valence electron?
Answers
Answer:
sodium has only one valance electron in valence shell
Calculate the concentration of the cobalt(ii) chloride hexahydrate solution titrated in the fine tritration experiment.
Answers
The concentration of the cobalt(II) chloride hexahydrate solution in this fine titration experiment is 0.05 M.
In order to calculate the concentration of the cobalt(II) chloride hexahydrate solution titrated in the fine titration experiment, you would need to know the volume and molarity of the titrant used and the volume of the cobalt(II) chloride hexahydrate solution being titrated.
To calculate the concentration, you can use the formula:
Concentration (in moles per liter) = moles of cobalt(II) chloride hexahydrate / volume of cobalt(II) chloride hexahydrate solution (in liters)
First, calculate the moles of cobalt(II) chloride hexahydrate by multiplying the volume of the titrant used (in liters) by its molarity.
Next, divide the moles of cobalt(II) chloride hexahydrate by the volume of the cobalt(II) chloride hexahydrate solution (in liters) to find the concentration.
For example, if you used 0.025 liters of a 0.1 M titrant to titrate 0.05 liters of the cobalt(II) chloride hexahydrate solution, the calculation would be:
Moles of cobalt(II) chloride hexahydrate
= 0.025 L x 0.1 M
= 0.0025 moles
Concentration = 0.0025 moles / 0.05 L
= 0.05 M
Therefore, the concentration of the cobalt(II) chloride hexahydrate solution in this fine titration experiment is 0.05 M.
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How many half-lives before there is less than 1% Uranium-238 left? Less than 1% Uranium235?
Answers
It takes approximately 6 half-lives for there to be less than 1% of Uranium-238 left and approximately 5 half-lives for there to be less than 1% of Uranium-235 left.
The concept of half-life is a fundamental aspect of radioactive decay. The half-life of a radioactive substance is the time it takes for half of the initial amount of the substance to decay. After one half-life, 50% of the substance remains, after two half-lives, 25% remains, and so on.
For Uranium-238, which has a very long half-life of about 4.5 billion years, it takes approximately 6 half-lives to reach less than 1% of the initial amount. This means that after each half-life, the amount of Uranium-238 is halved, and after six such halvings, less than 1% is left.
On the other hand, Uranium-235 has a shorter half-life of about 703.8 million years. Thus, it takes approximately 5 half-lives for Uranium-235 to reach less than 1% of the initial amount.
Knowing the number of half-lives required for a substance to reach less than 1% of its initial quantity is important in various scientific and practical applications, particularly in understanding radioactive decay and the behavior of radioactive materials over time.
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What chemical bond holds the nitrogenous base pairs together?
Answers
Between the two strands of DNA, a hydrogen bond (H-bond) holds the nitrogen bases together.
What is a chemical bond?
An enduring attraction between atoms or ions known as a chemical bond is what allows molecules and crystals to form. The bond may be created by the sharing of electrons in covalent bonds or by the electrostatic attraction of two oppositely charged ions, as in ionic bonds.
The two nitrogenous bases are joined by two hydrogen bonds. One of the hydrogen bonds is created between the oxygen atom of the keto group at C-4 of thymine and one of the amino group's hydrogen atoms at C-6 of adenine. The adenine's nitrogen atom at position 1 and the hydrogen atom connected to N-3 form another bond. DNA's double helix structure depends on the hydrogen bonds between adenine and thymine. They can be broken at high temperatures because they are not particularly strong bonds.
Because the breakage of the two hydrogen bonds between A and T requires less energy than the breakage of the three hydrogen bonds between G and C at G-C rich sites, the beginning of DNA replication and transcription frequently occurs at A-T rich sites.
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an iron nut and bolt are used to attach two zinc plates together on the underside of a boat. if this boat is to be used in the ocean, what might happen?
Answers
If the boat with the iron nut and bolt and zinc plates is used in the ocean, it is at risk of galvanic corrosion.
Is because the iron and zinc have different electrolysis voltages, so when a current passes through the water around the boat, it will strip away electrons from the zinc, leaving it vulnerable to corrosion.
To counteract this, a third metal, such as a sacrificial anode made of zinc, can be added to the circuit to act as a sacrificial anode, thereby protecting the boat from corrosion.
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Please answer my question I really need it now
Answers
Answer:
1 Li , Na, K, Rb, Cs
2 Co, V , Cr, Mn, Fe
3 Po, Te, Se, S, O
Which statement best describes the relationship between igneous and metamorphic rocks?
Metamorphic rocks are formed from melting igneous rocks.
O Metamorphic rocks and igneous rocks do not follow a rock cycle
Igneous rocks must go through the sedimentary process to change into metamorphic rocks.
Igneous rocks are chemically changed into metamorphic rocks because of high temperature and pressur
Answers
Answer:
Igneous rocks must go through the sedimentary process to change into metamorphic rocks. Igneous rocks are chemically changed into metamorphic rocks because of high temperature and pressure. Metamorphic rocks are formed from melting igneous rocks. Metamorphic rocks and igneous rocks do not follow a rock cycle.
Explanation:
hope this helps!
Answer:
C
Explanation:
It's igneous rocks must go through the sedimentary process answer thing
Why have rainforest plants adapted to be a different shape and size than desert plants?
A
because rainforest plants are only raised in zoos
B
because in a rainforest environment, adaptation can happen overnight
с
because rainforest plants and desert plants need to store the same amount of
water
because the rainforest environment is different than the desert environment
Answers
Answer:
option D is correct answer of this question
option D is correct answer of this questionbecause the rainforest environment is different than the desert environment
option D is correct answer of this questionbecause the rainforest environment is different than the desert environment hope it will help
The reason of why rainforest plants adapted to be a different shape as compared to the desert plants is because of option d. as the rainforest environment is different than the desert environment.
Adaption of the rainforest plants to the different shapes and size?
It can be like:
Drip tips - where plants contains leaves with pointy tips.Buttress roots - These contain large roots that have ridges that develop a large surface area. Epiphytes - It lives on the branches of trees high up in the canopy.hence, The reason of why rainforest plants adapted to be a different shape as compared to the desert plants is because of option d. as the rainforest environment is different than the desert environment.
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An old refrigerator is rated at 500 W how many kilowatt hours of electric energy what does refrigerator use in 30 days assume the refrigerator is running 12 hours per day
Answers
The refrigerator would use 180 kilowatt-hours (kWh) of electric energy over the course of 30 days, assuming it runs for 12 hours each day.
To calculate the kilowatt-hours (kWh) of electric energy used by the refrigerator in 30 days, we need to multiply the power rating by the total running time.
Given:
Power rating of the refrigerator = 500 W
Running time per day = 12 hours
Number of days = 30
First, we need to convert the power rating from watts to kilowatts:
Power rating = 500 W / 1000 = 0.5 kW
Next, we calculate the total energy used in kilowatt-hours (kWh) over the 30-day period:
Energy used = Power rating × Running time × Number of days
Energy used = 0.5 kW × 12 hours/day × 30 days
Energy used = 180 kWh
Therefore, the refrigerator would use 180 kilowatt-hours (kWh) of electric energy over the course of 30 days, assuming it runs for 12 hours each day.
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Which is a greater mass, 0.25 moles of carbon dioxide, CO2, or 1.5 x 1023 particles of carbon monoxide, CO?
Answers
0.25 moles of carbon dioxide has a greater mass which is equal to 11g.
There is a formula that reads,
"Mass = molecular mass × moles"
The molecular mass of carbon dioxide is 44 and remains constant.
Plugging in the equations we get,
Mass = 44 × 0.25
Mass of carbon dioxide = 11g.
Again, for mass of carbon monoxide, we get;
1 mole CO contains 6.022 × \(10^{23}\) molecules of CO.
So, mass of 6.022 × \(10^{23}\) molecules of CO = 28 g.
Therefore, mass of 1.5 × \(10^{23}\) molecules of CO,
(1.5×\(10^{23}\) ×28) / (6.022×\(10^{23}\)) = 6.97g ≈ 7g
Therefore, 0.25 moles of carbon dioxide has a greater mass.
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The volcano remains at level 4, the second-highest level on the
country’s volcano-alert system, which means a hazardous eruption
could happen in hours or days. Scientists say the threat of a major
eruption remains high because PHIVOLCS has
Answers
It appears to be related to a volcanic activity alert system in a certain country. The statement mentions that a volcano is currently at level 4, which is the second-highest level on the country's volcano-alert system.
A volcano is a graphical representation of the relationship between the energy changes and reaction progress in a chemical reaction. It is commonly used to describe acid-base reactions, where the reactants and products have different acid-base properties.
The volcano plot is a graph with the reaction rate or activity of a catalyst on the y-axis and the reaction-free energy or potential on the x-axis. It is named after its shape, which resembles a volcano with a peak representing the maximum reaction rate or activity.
The position of a reactant or catalyst on the volcano plot determines its ability to promote the reaction. If it is to the left of the peak, the reaction is thermodynamically favorable but kinetically slow. If it is to the right of the peak, the reaction is kinetically favorable but thermodynamically less favorable.
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The for the following reaction is -905 kJ for the forward reaction. List all possible changes that could be made to increase the production of NO.
Answers
The balanced equation for the reaction is:
4NH₃(g) + 5O₂(g) ⇌ 4NO(g) + 6H₂O(g)
The ΔHrxn value of -905 kJ/mol indicates that the forward reaction (reactants forming products) is exothermic, meaning that it releases energy.
To increase the production of NO, we need to shift the equilibrium towards the right side of the equation, i.e., we need to favor the forward reaction. There are several possible ways to achieve this:
Increase the concentration of reactants: Increasing the concentrations of NH₃ and O₂ will increase the likelihood of reactant molecules colliding and forming NO. This will shift the equilibrium towards the right side.
Decrease the concentration of products: Decreasing the concentration of NO and H₂O will reduce the likelihood of these molecules colliding and forming reactants. This will shift the equilibrium towards the right side.
Increase the temperature: Since the forward reaction is exothermic, increasing the temperature will favor the reverse reaction (products forming reactants). However, the reaction will still shift towards the right side since the forward reaction releases more energy than the reverse reaction absorbs. Thus, increasing the temperature will increase the production of NO.
Decrease the pressure: The reaction involves gases, so decreasing the pressure will shift the equilibrium towards the side with fewer moles of gas. Since there are more irregular moles of gas on the right side of the equation, decreasing the pressure will shift the equilibrium towards the right side and increase NO production.
Adding a catalyst: A catalyst can increase the reaction rate without being consumed in the reaction itself. This will increase the speed at which the reaction reaches equilibrium and may help shift the equilibrium toward the right side.
Overall, any change that increases the concentration of reactants, decreases the concentration of products, increases the temperature, decreases the pressure, or adds a catalyst will increase the production of NO.
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An ammonia buffer solution contains 0.25 M NH4+NHX4X+
and 0.22 M NH3NHX3
. The pKa of ammonium is 9.24. What is the pH of the buffer?
Answers
To find the pH of the buffer, we need to use the Henderson-Hasselbalch equation:
\(pH = pKa + log([NH_{3} ]/[NH_{4} +])\)
where [\(NH_{3}\)] is the concentration of ammonia and\([NH_{4}+]\) is the concentration of ammonium.
First, we need to calculate the concentration of ammonium ion \((NH_{4} +)\)using the dissociation equilibrium of ammonium:
\(NH_{4}+ + H_{2}O = NH_{3} + H_{3} O+\)
The equilibrium constant for this reaction is:
\(Ka = [NH_{3}][H_{3}O+]/[NH_{4} +]\)
Since we know the pKa of ammonium (9.24), we can calculate the Ka:
\(Ka = 10^{-pKa} = 10^{-9.24} = 4.38 * 10^{-10}\)
Now, we can use the concentrations of\(NH_{4} +\)and \(NH_{3}\)given in the problem to calculate the concentration of \(H_{3}O+:\)
\(Ka = [NH_{3} ][H_{3} O+]/[NH_{4} +]\)
\(4.38 * 10^{-10} = (0.22-x)*/(0.25+x)\)
where x is the concentration of \(H_{3}O+\) in M.
Solving for x, we get:
\(x = 3.3 * 10^{-9}\) M
So, the concentration of \(H_{3}O+\) is \(3.3 * 10^{-9}\) M. Using this value and the concentrations of \(NH_{4}+\) and \(NH_{3}\), we can now calculate the pH of the buffer:
\(pH = pKa + log([NH_{3} ]/[NH_{4} +])\)
\(pH = 9.24 + log(0.22/0.25)\)
pH = 9.24 - 0.048
pH = 9.192
Therefore, the pH of the ammonia buffer solution is approximately 9.192.
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how many unpaired electrons are in br+?a. 5b. 2c. 0d. 3e. 1
Answers
There is only 1 unpaired electron in Br⁺. The correct answer is e. 1.
Unpaired electrons are electrons that occupy an orbital by themselves, rather than being paired with another electron in the same orbital. This can occur in atoms or molecules that have an odd number of electrons, or in atoms or molecules that have electron configurations that allow for unpaired electrons.
Br⁺ has a total of 34 electrons, and when we fill up the electron orbitals, we are left with one unpaired electron in the 4p orbital. The electron configuration for Br⁺ is [Ar] 3d10 4s2 4p5, with the one unpaired electron in the 4p orbital.
Therefore, the correct answer is e. 1.
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T or F Antoine Lavoisier formulated the atomic theory
Answers
Antoine Lavoisier formulated the atomic theory. This statement is False.
While Antoine Lavoisier made significant contributions to the development of modern chemistry, he did not formulate the atomic theory.
The atomic theory was first proposed by the English chemist John Dalton in the early 19th century.
Dalton's atomic theory proposed that all matter is made up of tiny, indivisible particles called atoms, which have unique properties based on their element.
Dalton also suggested that chemical reactions involve the rearrangement of atoms, but do not create or destroy them.
Lavoisier, on the other hand, is best known for his work on the law of conservation of mass and the development of the modern system of naming chemical compounds.
He was a key figure in the transition from alchemy to modern chemistry and made many significant contributions to the field, but he did not formulate the atomic theory.
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the temperatures (degrees celsius) on april 12, 2022, of a group of 16 african cities were obtained. which level of measurement is temperature in degrees celsuis?
Answers
Temperature in degrees Celsius is considered an interval level of measurement.
In the context of temperature, interval measurement means that the differences between temperature values are meaningful and can be quantitatively compared. It allows for the calculation of temperature differences and the determination of intervals between temperature values. However, there is no inherent meaningful zero point in degrees Celsius. For example, a temperature of 0 degrees Celsius does not indicate the complete absence of heat. Therefore, ratios of temperature values, such as doubling or halving, do not hold the same significance as they would in a ratio level of measurement.
It's important to note that the choice of temperature scale, such as Celsius, Fahrenheit, or Kelvin, is a matter of convention and does not affect the level of measurement.
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The level of measurement for temperature in degrees Celsius is interval level of measurement.
What is level of measurement?
In statistics, the level of measurement describes the nature of the variable or data. In research studies, researchers make use of different data types based on their nature.
Four levels of measurement are used, which are nominal, ordinal, interval, and ratio levels.
These levels vary in terms of the characteristics of the variables measured.Nominal level of measurement refers to qualitative variables, which are categorized and identified based on their characteristics.
Ordinal level of measurement refers to variables that can be ordered, and the difference between them is not necessarily constant.
Interval level of measurement involves variables that are ordered, and the difference between them is constant.
Ratio level of measurement involves variables that are ordered, and the difference between them is both constant and meaningful.
Based on the above discussion, the level of measurement for temperature in degrees Celsius is interval level of measurement.
This is because temperature in degrees Celsius involves values that are ordered, and the difference between them is constant.
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Describe how continents change over time.
Answers
When the equation for the reaction represented above is balanced and all coefficients are reduced to lowest whole number terms, the coefficient for H 2O (g) is : _________
Answers
When the equation for the reaction representation above is balanced and all coefficients are reduced to the lowest whole-number terms, the coefficient for O₂ is 5.
What makes an equation "balanced"?An equation for a chemical reaction is said to be balanced if both the reactants and the products have the same number of atoms and total charge for each component of the reaction. In other words, both sides of the reaction have an equal balance of mass and charge.
Note that a chemical equation that is balanced has equal amounts of each element's atoms on both sides of the equation and conserves mass.
Based on the equation given O₂ will have 5unit or mole if it is balanced because the C₃ will share with O₂.
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See full question below
C3H8 + O2 -> CO2 + H2O
When the equation for the reaction representation above is balanced and all coefficients are reduced to the lowest whole-number terms, the coefficient for O2 is:
If 24k gold is the highest purity (100%), then a 6 Karat piece of gold jewelry would contain what percentage of gold?
Answers
Answer:
25% gold.
Explanation:
6 is 25 percent of 24, so 6 karat gold would be 25% gold.
What element have 5 energy levels of electrons. Which as an atom the last electron is found in the 5p^3
Answers
Answer:
I hope this answer is correct
Explanation:
Element having electronic configuration 1s
2
,2s
2
,2p
6
,3s
2
,3p
6
,3d
10
,4s
2
,4p
6
,4d
10
,5s
2
,5p
3
Placing a sample of iron (II) oxide into a graduated cylinder makes the water volume increase 12.0 ml. The weight of the sample is 76.6g. What is it’s density? (Round to the nearest hundredths)
Answers
Answer:
The answer is 6.83 g/mLExplanation:
The density of a substance can be found by using the formula
\(density = \frac{mass}{volume} \\\)
From the question
mass of iron (II) oxide = 76.6 g
volume = 12 mL
We have
\(density = \frac{76.6}{12} \\ = 6.3833333...\)
We have the final answer as
6.83 g/mL to the nearest hundredthHope this helps you
Answer:
it 76.6
Explanation:
cause it is what it is
When a company is to calculate the selling price of their products, they set up a product calculation. There are five benefits to the business when making a product calculation. Explain these five benefits.
Answers
Answer:
The pricing strategy is an important element in setting up the selling price of a product.
Explanation:
The pricing strategy is an important consideration while fixing up the selling price of product manufactured. When setting up a selling price of a product, the companies set up product calculation. Businesses should decide the pricing strategy before they advertise the products to the customers.
There are mainly 5 benefits to the businesses while doing a product calculation. They are:
--- Doing competition based pricing enables the company to compete with the rival companies product and is based on the market based study. Competition pricing is a useful tool for the retailers as well as the small businesses.
--- Doing a cost plus pricing helps the total cost of making the product and also an add up in the market in order to determine the pricing of the product.
--- Dynamic pricing :
Dynamic pricing is a non static pricing. Dynamic pricing is an efficient method for the market based on the supply and demand.
--- Penetration pricing :
Penetration pricing is used by the large companies which is used to capture the market share by the setting product prices at the below market level so as to gain customers.
--- Doing a research for the price skimming helps the company to set up the accurate price for the product rather than readjusting the prices of the product later on based on the demand and the supply.
what volume of solution can be prepared using 7.55g of KCl if the final molarity is 0.55M?(ans 0.18L)
Answers
0.18 L of solution can be prepared using 7.55g of KCl if the final molarity is 0.55M.
Give a brief account on Molarity.Molarity (M) is known to be the amount of a substance in a given volume of solution which is usually is defined as the number of moles of solute per liter of solution.
Both molarity and molarity are measures of the concentration of a chemical solution. The main difference between the two is mass and volume. Molarity refers to the moles of solute to the mass of the solvent, and molarity refers to the moles of solute to the volume of the solution.
Let's calculate no. of moles first:
No. of moles = Mass/Molecular mass
Mass of given KCl = 7.55 g
Molecular mass of KCl = 74.5513 g/mol
No. of moles = 7.55/74.5513
No. of moles = 0.100 mol
Now, for the calculation of molarity:
Molarity = No. of moles/V of solution
0.55 = 0.100/V
V = 0.100/0.55
V = 0.18 L
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For the following reaction, 6.74 grams of chlorine gas are mixed with excess iron. The reaction yields 8.73 grams of iron(III) chloride .
Answers
Answer:22.22
Explanation:22.22
Question 20 0/1 pts What is the frequency of a light wave with the wavelength of 680 nm? 'Reminder: the speed of light is 3.00 X 10 m/s
Answers
Answer:
\(4.4*10^{14}\)Hz
Explanation:
Identify the number of atoms for each element in 8Sio2?
Answers
Explanation:
4.1 The Chemical Equation
LEARNING OBJECTIVES
Define chemical equation.
Identify the parts of a chemical equation.
A chemical reaction expresses a chemical change. For example, one chemical property of hydrogen is that it will react with oxygen to make water. We can write that as follows:
hydrogen reacts with oxygen to make water
We can represent this chemical change more succinctly as
hydrogen + oxygen → water
where the + sign means that the two substances interact chemically with each other and the → symbol implies that a chemical reaction takes place. But substances can also be represented by chemical formulas. Remembering that hydrogen and oxygen both exist as diatomic molecules, we can rewrite our chemical change as
H2 + O2 → H2O
This is an example of a chemical equation, which is a concise way of representing a chemical reaction. The initial substances are called reactants, and the final substances are called products.
Unfortunately, it is also an incomplete chemical equation. The law of conservation of matter says that matter cannot be created or destroyed. In chemical equations, the number of atoms of each element in the reactants must be the same as the number of atoms of each element in the products. If we count the number of hydrogen atoms in the reactants and products, we find two hydrogen atoms. But if we count the number of oxygen atoms in the reactants and products, we find that there are two oxygen atoms in the reactants but only one oxygen atom in the products.
What can we do? Can we change the subscripts in the formula for water so that it has two oxygen atoms in it? No; you cannot change the formulas of individual substances because the chemical formula for a given substance is characteristic of that substance. What you can do, however, is to change the number of molecules that react or are produced. We do this one element at a time, going from one side of the reaction to the other, changing the number of molecules of a substance until all elements have the same number of atoms on each side.
To accommodate the two oxygen atoms as reactants, let us assume that we have two water molecules as products:
H2 + O2 → 2H2O
The 2 in front of the formula for water is called a coefficient. Now there is the same number of oxygen atoms in the reactants as there are in the product. But in satisfying the need for the same number of oxygen atoms on both sides of the reaction, we have also changed the number of hydrogen atoms on the product side, so the number of hydrogen atoms is no longer equal. No problem—simply go back to the reactant side of the equation and add a coefficient in front of the H2. The coefficient that works is 2:
2H2 + O2 → 2H2O
There are now four hydrogen atoms in the reactants and also four atoms of hydrogen in the product. There are two oxygen atoms in the reactants and two atoms of oxygen in the product. The law of conservation of matter has been satisfied. When the reactants and products of a chemical equation have the same number of atoms of all elements present, we say that an equation is balanced. All proper chemical equations are balanced. If a substance does not have a coefficient written in front of it, it is assumed to be 1. Also, the convention is to use all whole numbers when balancing chemical equations. This sometimes makes us do a bit more “back and forth” work when balancing a chemical equation.
If 359 mL of a gas were contracted to only 269 mL, what would be the initial
temperature of it if it measured 422 K after the change?
Answers
A gas that initially had a temperature of 422 K and was reduced to only 269 mL would now have an initial temperature of 563.19 K.
Volume at start: 359 mL
Volume completed: 269 mL
422 K is the final temperature.
Temperature at the start =?
Charle's Law can be used to resolve the issue. Charles Law states that with constant pressure and molecular number, the volume of a given amount of a gas is directly proportional to its temperature.
V₁/T₁ = V₂/T₂
Initial volume: V1
Initial temperature is T1.
Final volume is V2.
T2 = Actual temperature.
We will now enter the values into the formula.
V₁/T₁ = V₂/T₂
T₁ = V₁T₂ / V₂
T1 = 359 ml 269 ml / 422 K
T1=151498 ml.K/ 269 ml
T₁ = 563.19 K
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how many electrons does Helium need to have a full outer shell
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Answer:
i dont no about this one
Explanation:
give the neutral formula unit for the combination of the following: calcium and no3–.
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The neutral formula unit for the combination of calcium and NO₃⁻ is Ca(NO₃)₂. Calcium is a metal that belongs to group 2 of the periodic table, and it has a +2 charge. NO₃⁻ is a polyatomic ion that has a -1 charge.
When these two elements combine, they form an ionic compound through electrostatic attraction. The calcium cation and the nitrate anions combine in a 1:2 ratio to form the neutral compound Ca(NO₃)₂. This formula unit represents the simplest ratio of atoms in the compound and indicates that one calcium ion is combined with two nitrate ions.
So, the neutral formula unit for the combination of calcium (Ca) and nitrate (NO₃⁻) is Ca(NO₃)₂. In this compound, calcium has a charge of +2, while each nitrate ion has a charge of -1. To create a neutral formula unit, we need two nitrate ions for each calcium ion to balance the charges.
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