Tellurium is a period 5 chalcogen. Selenium is a period 4 chalcogen. If the only factor affecting ionization energies was the nuclear charge, then electrons would be easier to remove (ionize) from Se than Te. Experimentally the opposite is true. It takes 941.0 kJ/mol of energy to ionize the outermost electron from Se while it only takes 869.3 kJ/mol to ionize from Te. A good model should account for this. Quantum mechanical calculations do predict this but require access to sophisticated software, large amounts of computing power and technical expertise. Slater suggested that some simple empirical rules that take into account electron electron repulsion (or shielding) could give a good estimate of the effective nuclear charge (Zeff). The Zeff for the outermost electron in Te is . The Zeff for the outermost electrons in Se is . According to Slater's calculation of effective nuclear charge (does or does not) predict the correct ordering of ionization energies for Se and Te. A better means of rationalizing ionization energies is to include the atomic as follows: [Z subscript e f f end subscript over r squared] . For Te, r = 136 pm and for Se r = 117 pm. This new model (does or does not) predict the correct ordering of first ionization energies for Se and Te.

Biotechnology is the use of living organisms or other biological systems in the manufacture of drugs or other products or for environmental management, as in waste recycling: includes the use of bioreactors in manufacturing, microorganisms to degrade oil slicks or organic waste, genetically engineered bacteria to produce human hormones, and monoclonal antibodies to identify antigens.

Biotech offers the possibility of improving human health, the environment, and agriculture while creating more sustainable modes of production.

Answer:

mass = 25.0 g

density = 1.48 g / cm^3

volume = ?

volume = mass / density

volume = 25 / 1.48

volume = 16.892 cm^3

Answer:

conservation of mass

Answer:

According to conservation of matter, there should be equal amounts of all elements on both the reactant and product side.

Reactant:

1 Ca

1 C

1 O

Product:

1 Ca

1 C

3 O

Therefore, your friend is right because the law of conservation of matter is not followed in this chemical equation.

Explanation:

The reaction order and specific reaction rate constant can be determined by performing the kinetics experiment on irreversible polymerization A. Kinetic experiments can be used to investigate the rate and mechanism of chemical reactions. Chemical kinetics is the study of chemical reactions' speed and pathway.

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Answer:

The correct answer is 1) 56 ml and 2) 0.314 M

Explanation:

1. The reaction taking place in the given case is,  

HClO₃ + KOH ⇒ KClO₃ + H2O, the molarity of HClO₃ given is 0.100 M, the molarity of KOH given is 0.140 M and the volume of KOH given is 40 ml, there is a need to find the volume of HClO₃.  

Therefore, the mole of HClO₃ = mole of KOH

= MHClO₃ × VHClO₃ = MKOH × VKOH

= 0.100 M × VHClO₃ = 0.140 M × 40 ml

VHClO₃ = 0.140 M × 40 ml/0.100 M

VHClO₃ = 56 ml.  

2. The reaction taking place is,  

2HNO₃ + Ba(OH)₂ ⇒ Ba(NO₃)₂ + 2H₂O

The volume of HNO₃ given is 25 ml, the molarity of Ba(OH)2 is 0.250 M, the volume of Ba(OH)2 is 15.7 ml, the n or the number of moles of HNO₃ is 2, and the n of Ba(OH)2 is 1, the concentration or M of HNO₃ is,  

M₁V₁/n₁ = M₂V₂/n₂

M₁ × 25/ 2 = 0.25 × 15.7/1

M₁ or molarity of HNO₃ = 0.314 M

1. The volume of HClO₃ required to neutralize the KOH is 56.0 mL

2. The concentration of the original HNO₃ solution is 0.314 M

1.

First, we will write a balanced chemical equation for the reaction

The balanced chemical equation for the reaction is

HClO₃ + KOH → KClO₃ + H₂O

This means,

1 mole of HClO₃ is required to neutralize 1 mole of KOH

From the titration formula

\(\frac{C_{A}V_{A} }{C_{B}V_{B}} = \frac{n_{A}}{n_{B}}\)

Where

\(C_{A}\) is the concentration of acid

\(C_{B}\) is the concentration of base

\(V_{A}\) is the volume of acid

\(V_{B}\) is the volume of base

\(n_{A}\) is the mole ratio of acid

\(n_{B}\) is the mole ratio of base

From the given information,

\(C_{A} = 0.100 \ M\)

\(C_{B} = 0.140 \ M\)

\(V_{B} = 40.0 \ mL\)

From the balanced chemical equation

\(n_{A} = 1\)

\(n_{B} =1\)

Putting the values into the formula, we get

\(\frac{0.100 \times V_{A} }{0.140 \times 40.0} = \frac{1}{1}\)

∴ \(0.100 \times V_{A} = 0.140 \times 40.0\)

\(V_{A}=\frac{0.140\times 40.0}{0.100}\)

\(V_{A}=\frac{5.60}{0.100}\)

\(V_{A}=56.0 \ mL\)

Hence, the volume of HClO₃ required to neutralize the KOH is 56.0 mL

2.

First, we will write the balanced chemical equation for the reaction

The balanced chemical equation for the reaction is

2HNO₃ + Ba(OH)₂ → Ba(NO₃)₂ + 2H₂O

This means, 2 mole of HNO₃ is required to neutralize 1 mole Ba(OH)₂  

From the given information,

\(V_{A} = 25.0\ mL\)

\(C_{B} = 0.250 \ M\)

\(V_{B} = 15.7 \ mL\)

From the balanced chemical equation

\(n_{A} = 2\)

\(n_{B} =1\)

Also, Using the titration formula

\(\frac{C_{A}V_{A} }{C_{B}V_{B}} = \frac{n_{A}}{n_{B}}\)

We get

\(\frac{C_{A} \times 25.0 }{0.250 \times 15.7} = \frac{2}{1}\)

Then,

\(C_{A} = \frac{2\times 0.250 \times 15.7} {1 \times 25.0}\)

\(C_{A} =\frac{7.85}{25.0}\)

\(C_{A} =0.314 \ M\)

Hence, the concentration of the original HNO₃ solution is 0.314 M

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There were 0.166 moles of oxygen, O, in the sample.

Given:

The unknown compound with a mass of 5.00 grams.

In 5.00 grams of compound contained 0.167 moles of C and 0.333 moles of hydrogen.

To find:

The moles of oxygen in 5.00 grams of an unknown compound.

Solution:

Moles of carbon in 5.00 grams of compound = 0.167 mol

Mass of carbon in 5.00 grams :

\(=0.167 mol\times 12.0107 g/mol=2.01 g\)

Moles of hydrogen in 5.00 grams of compound = 0.333 mol

Mass of hydrogen in 5.00 grams :

\(= 0.333 mol\times 1.00784 g/mol=0.336 g\)

Mass of oxygen in 5.00 grams of compound:

\(= 5.00 g - 2.01 g - 0.336 g = 2.654 g\)

Moles of oxygen in 2.654 g :

\(=\frac{2.654 }{15.999 g/mol} \\\\=0.1658 mol\approx 0.166 mol\)

There were 0.166 moles of oxygen, O, in the sample.

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we would need 2625.13 grams (or 2.62513 kilograms) of NaCl.

To calculate the mass of NaCl required to produce a 26.4 mol/L solution with a 1.7 L volume, we need to use the formula that relates the mass of solute, moles of solute, and molarity:Molarity (M) = moles of solute / liters of solution Rearranging this formula, we get:moles of solute = Molarity (M) x liters of solutionWe can use this formula to find the moles of NaCl needed:moles of NaCl = 26.4 mol/L x 1.7 L = 44.88 molNow, we can use the molar mass of NaCl to convert from moles to grams. The molar mass of NaCl is 58.44 g/mol:mass of NaCl = moles of NaCl x molar mass of NaClmass of NaCl = 44.88 mol x 58.44 g/mol = 2625.13 gTo produce a 26.4 mol/L solution with a 1.7 L volume.

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Answer:

its sodium hydroxide

Explanation:

Answer:

348 inches³

Explanation:

From our previous knowledge of  units conversion:

We know that 1000 cm³ makes 1 Liter.

Thus, for  a 5.70 L automobile engine in cubic meters will be:

= 5.70 × 1000 cm³

= 5700 cm³

Now, the displacement of the automobile in cubic inches provided that 1 inch = 2.534 cm is:

⇒ 5700× (1/ (2.54)³) in³

= 5700×0.0610 in³

= 347.7 in³

≅ 348 inches³

The temperature increase from 20 °C to 46 °C indicates that the reaction between zinc and copper sulfate solution is exothermic, with heat being released into the surroundings.

In the given reaction between zinc and copper sulfate solution, the temperature change can provide insights into the type of heat change occurring during the reaction. Based on the provided information, the initial temperature of the copper sulfate solution was 20 °C, and the final temperature of the mixture after the reaction was 46 °C.

The temperature increase observed in this reaction indicates an exothermic heat change. An exothermic reaction releases heat energy into the surroundings, resulting in a temperature rise. In this case, the reaction between zinc and copper sulfate solution is exothermic because the final temperature is higher than the initial temperature.

During the reaction, zinc displaces copper from copper sulfate to form zinc sulfate and copper metal. This displacement reaction is known as a single displacement or redox reaction. Zinc is more reactive than copper and therefore replaces copper in the compound.

The formation of new chemical bonds during the reaction releases energy in the form of heat. This energy is transferred to the surroundings, leading to an increase in temperature. The heat released is greater than the heat absorbed, resulting in a net increase in temperature.

The exothermic nature of this reaction can be explained by the difference in bond energies between the reactants and products. The breaking of bonds in the reactants requires energy input, while the formation of new bonds in the products releases energy.

In this case, the energy released during the formation of zinc sulfate and copper metal is greater than the energy required to break the bonds in copper sulfate and zinc.

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Following the composition by mass, the molecular formula of monosodium glutamate would be \(C_7H_8O_4NNa\)

The empirical formula can first be derived such that:

C = 51/12             = 4.25

H = 4.778/1           = 4.77

O = 37.8/16       = 2.36

N = 8.29/14       = 0.59

Na = 13.60/23      = 0.59

Dividing by the smallest (0.59):

C = 7

H = 8

O = 4

N = 1

Na = 1

Hence, the empirical formula would be \(C_7H_8O_4NNa\)

Molar mass of empirical formula = 12x7 + 8x1 + 16x4 + 14 + 23

                                                         = 195

Recall that: , (\(C_7H_8O_4NNa\))n = molecular formula

                                   Where n = molar mass/empirical formular mass

Molar mass/empirical formular mass = 169/195

                                                       = 0.87

                                                          ≈ 1

Thus, (\(C_7H_8O_4NNa\)) x 1 = \(C_7H_8O_4NNa\)

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The helium sample will occupy a volume of 11.12 L if the pressure is reduced to 5.15 atm while maintaining the temperature at 20 °C.

The ability of monoprotic acids to donate one hydrogen atom or proton to their aqueous solution as opposed to diprotic acids to provide two hydrogen atoms or protons is the primary distinction between the two types of acids.

The pressure and volume of a gas are related by the following equation, known as Boyle's law:

P1V1 = P2V2

where P1 and V1 are the initial pressure and volume, and P2 and V2 are the final pressure and volume, respectively.

Using this equation, we can solve for V2:

P1V1 = P2V2

V2 = (P1V1) / P2

Plugging in the values given in the problem, we get:

V2 = (5.79 atm x 9.89 L) / 5.15 atm

V2 = 11.12 L

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The situation where erosion is likely to occur is B. A bare hillside with loose, dry soil

Erosion is an ongoing process of soil displacement when airflows or water currents move through landforms. Examples occur on hillside areas which have no plants, grasses, shrubs, or anything else to stabilize the dry dirt underneath – making it easy for wind and rainfall to literally transport the surface materials in downward cascades.

Unfortunately, this can yield serious consequences - from impoverished fertility to extra sediments being added to nearby creeks and rivers, to demolishing the infrastructure located at the base of the hill.

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Options include;

B. The study of matter and energy.

Because physical science is everything that doesn't include organic things.

The  study of matter and energy among the following  best describes physical science.

Matter in chemistry, is defined as any kind of substance that has mass and occupies space that means it possess volume .Matter is composed up of atoms which may or not be of same type.

Atoms are further made up of sub atomic particles which are the protons ,neutrons and the electrons .The matter can exist in various states  of substances such as solids, liquids and gases depending on the conditions of  the temperature and  the pressure.

The states of matter are inter convertible into each other by changing the parameters of temperature and pressure.Matter is always conserved by law of conservation of matter.The law was proposed by Antoine Lavoisier.

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Acid rain can be caused by all of the following except earthquakes.

Rain has a naturally acidic pH range of 5 to 6. This acidity is caused by sulfur dioxide, nitrogen oxide, and carbon dioxide, which react with oxygen gas and water in the atmosphere to form sulfuric, nitric, and carbonic acids. Acid rain is generated when the atmosphere is overly polluted by these oxides, notably sulfur and nitrogen oxides. Acid rain is the major cause of building deterioration, metal corrosion, and the breakdown of ecological balance.

Acid rain is defined as rain or any other form of precipitation that is unusually acidic, containing high quantities of hydrogen ions. Most water, including drinking water, has a neutral pH of 6.5 to 8.5, however acid rain has a pH lower than this, ranging from 4-5 on average.

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Answer:

C)2 mole Cu(NO3)2 / 2 mole Fe

Explanation:

I'm pretty sure.

When iron is combined with copper (1) nitrate, it produces iron (II) nitrate and copper. The following could NOT be a mole ratio in this chemical reaction is:

D) 1 mole Fe(NO₃)₂ / 1 mole Fe

To determine which of the given mole ratios could NOT be part of the chemical reaction between iron and copper(1) nitrate, we need to write the balanced chemical equation for the reaction and then compare it to the given ratios.

The balanced chemical equation for the reaction is:

Fe + Cu(NO₃)₂ → Fe(NO₃)₂ + Cu

A) 1 mole Fe / 2 mole Cu

This mole ratio is consistent with the balanced chemical equation, where 1 mole of Fe reacts with 2 moles of Cu(NO₃)₂ to produce 1 mole of Fe(NO₃)₂ and 1 mole of Cu. So, this ratio could be part of the chemical reaction.

B) 1 mole Fe(NO₃)₂ / 2 mole Cu

This mole ratio is also consistent with the balanced chemical equation, where 1 mole of Fe(NO₃)₂ is produced by reacting 2 moles of Cu(NO₃)₂. So, this ratio could be part of the chemical reaction.

C) 2 mole Cu(NO₃)₂ / 2 mole Fe

This mole ratio is consistent with the balanced chemical equation, where 2 moles of Cu(NO₃)₂ react to produce 2 moles of Fe(NO₃)₂. So, this ratio could be part of the chemical reaction.

D) 1 mole Fe(NO₃)₂ / 1 mole Fe

This mole ratio implies that 1 mole of Fe(NO₃)₂ is produced by reacting with 1 mole of Fe, which is not consistent with the balanced chemical equation. The equation shows that 1 mole of Fe reacts with 1 mole of Cu(NO₃)₂ to produce 1 mole of Fe(NO₃)₂ and 1 mole of Cu. Therefore, this ratio could NOT be part of the chemical reaction.

So, the correct answer is:

D) 1 mole Fe(NO₃)₂ / 1 mole Fe

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Answer:

will be 9.7 Liters

Explanation:

If you have 640 grams of an unstable isotope. The half-life of the isotope is 10 days. After 30 days it become 80 g.

The half life time is defined as that time in which the substance reduced to half of its quantity.

Or, the time required by the substance to reduced to its half of the concentration is termed as Half life time.

Given,

Mass of unstable Isotope = 640 g

The half-life of the isotope = 10 days

We have to calculate the the mass of unstable isotope after 30 days.

As we know that,

10 days = One half life time

1 days = 1/ 10 half life time

30 days = 30 / 10 half life time = 3 half life time

Thus, in first half life period it reduced to 640 / 2 = 320 g

In second half life period it reduced to 320 / 2 = 160 g

In third half life period it reduced to 160 / 2 = 80 g

Thus, we concluded that if you have 640 grams of an unstable isotope. The half-life of the isotope is 10 days. After 30 days it become 80 g.

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The amount of heat energy absorbed when 200 grams of water are heated from 20 C to 60 C is 33,440 Joules.

To find the amount of heat energy absorbed when 200 grams of water are heated from 20 C to 60 C, we can use the equation Q = mcAT.
First, we need to find the value of m, which is the mass of the water in grams. In this case, it is given as 200 grams.
Next, we need to find the value of AT, which is the change in temperature in degrees Celsius.

This can be calculated by subtracting the initial temperature from the final temperature, which gives us 60 C - 20 C = 40 C.
The specific heat capacity of water, C, is given as 4.18 Joules per gram per degree Celsius.
Now we can plug in the values into the equation:
Q = mcAT
Q = (200 g) x (4.18 J/g°C) x (40°C)
Q = 33,440 J
Therefore, the amount of heat energy absorbed when 200 grams of water are heated from 20 C to 60 C is 33,440 Joules.

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Answer:

First of all they are super tiny particles of neutrons, electrons and protons. Then they come together to organize a structure of atom. Atoms come together to form a molecule and smaller molecules work together to form macromolecules. Thus, how they organize and form building blocks of a substance.

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Answer:

group. hfdzybidddiklllnjjooolll

Answer:

An organ system

Explanation:

:>

Answer:

Explanation: that decays by emitting an electron  particle the resulting nuclide is zinc-64. and yeah

Answer:

98

Explanation:

Based on the reaction:

NaOH + H2SO4 → NaHSO4 + H2O

Where 1 mole of the base (NaOH) reacts per mole of the acid (H2SO4)

The formula of equivalent weight is:

Equivalent weight = Molecular mass / Number of equivalent moles

Where Molecular mass of sulfuric acid is 98g/mol

And number of equivalent moles = 1 -Because 1 mole of acid reacts per mole of base

Equivalent weight is:

98 / 1 =

98

Answer:

Alcohol is an Organic Compounds with a hydroxyl group (–OH) bonded to a carbon atom, whereas ether is an Organic Compounds with an oxygen atom that is bonded to two carbon atoms. The major difference between alcohol and ether is the absence of OH groups in the ether that are present in alcohol.

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