An unknown mass of silver is heated to a temp of 98. 75c and then placed into a calorimeter containing 250g of water st 6. 5c. The silver and the water reach thermal equilibrium at 23. 35c. What is the mass of the silver sample?

Answer:

Protons:

- positive

- aka cation

- in the nucleus along with the neutrons

Electrons:

- negative

- aka anion

- situated in the orbital shells/configuration levels (there are many names)

Answer:

The number of valence electrons

Cephalin, also known as phosphatidylethanolamine, is a phospholipid found in cell membranes. It consists of a glycerol backbone, two fatty acid chains attached to the first and second carbons (C1 and C2), and a phosphoethanolamine group linked to the third carbon (C3).

To draw the structure of cephalin with oleic acid on C2, start by drawing the glycerol backbone, which is a three-carbon chain with hydroxyl groups (OH) attached to each carbon. Next, attach oleic acid to the C2 position. Oleic acid is an unsaturated fatty acid with the formula CH3(CH2)7CH=CH(CH2)7COOH, which has one cis double bond between carbons 9 and 10.
At the C1 position, add another fatty acid, typically a saturated fatty acid like palmitic or stearic acid. Finally, connect the phosphoethanolamine group to the C3 position of the glycerol backbone. This group consists of a phosphate (PO4) attached to the hydroxyl group at C3, with an ethanolamine (NH2CH2CH2OH) linked to the phosphate.
In summary, the structure of cephalin with oleic acid on C2 consists of a glycerol backbone with oleic acid at C2, another fatty acid at C1, and a phosphoethanolamine group at C3. This phospholipid plays a vital role in cell membrane structure and function.

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Answer:

organisms in rain water and the number of organisms in pond water because the dependant variable never changes

Explanation:

because the dependant variable never changes

Answer:

Plastilina inteligente. Cambia de color en función de la temperatura ambiental. ...

Plastilina vegetal. ...

Plastilina para bebés. ...

Plastilina mágica. ...

Plastilina sin gluten. ...

Plastilina gris. ...

Plastilina magnética. ...

Plastilina Slime.

Explanation:

Answer: Answer

Iron is a chemical element with symbol Fe and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in front of oxygen, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust.

Explanation:

Hope this helps!

Answer:

iron:

group 8

4 orbitals

electrons per shell:2,8,14,2

26 electrons

8 valence electrons.

Explanation:

iron is in the 8th group in the periodic table because it is a transition metal and their valence shells have 8 electrons.

It has 4 electron shells because the first one can hold two electrons, the second has 8 and so on.

The total number of electrons is 26, which is equal to number of protons.

Valence electrons are in the outermost shell.

Answer:

Difference in temperature.

Explanation:

Conduction is the movement of heat energy through a substance or from one substance to another by direct contact of atoms and molecules. Heat moves directly from one molecule to another. The heat energy speeds up the movement of the atoms and they collide with other molecules setting them into faster motion.

The fraction of the strontium-90 absorbed in 1963 that remained in people's bones in 1994 is approximately 0.1507 or 15.07%.

The half-life of strontium-90 is 27 years.

Therefore, we can use the following formula to calculate the fraction of strontium-90 that remained in people's bones in 1994:

fraction = (1/2)^(t/h)where t is the time elapsed and h is the half-life of the substance.

In this case, t = 1994 - 1963 = 31 years, and h = 27 years.

So, the fraction of strontium-90 that remained in people's bones in 1994 is:

fraction = (1/2)^(31/27)≈ 0.1507 (rounded to 3 decimal places)

Therefore, the fraction of the strontium-90 absorbed in 1963 that remained in people's bones in 1994 is approximately 0.1507 or 15.07%.

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For getting an indication whether a chemical reaction or chemical change has taken place, if  B)Heat is given off then chemical reactions occur. So,correct option is B.

Chemical reactions are surrounding us, from the digestion of food in our body to how the light we get from the sun is the consequence of compound responses. Prior to starting with compound responses, realizing about physical and synthetic changes is significant

Option A can't be the response is dissolving is an actual change. No substance response occurred.

Option B is the response as it is an EXOTHERMIC reaction so intensity will be emitted.

Option C can't be the response as dissolving is essentially ions becoming particles, not a synthetic response by which a reactant responds with one more reactant to shape an item.

Option D can't be the response. Same explanation with respect to why An isn't the response.

Hence, correct option is B.

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(Complete question) is:

When determining whether a chemical reaction has taken place, you observe and look for several indicators. Which would be considered an indication that a chemical reaction or chemical change has taken place? A) Solid melts. B) Heat is given off. C) Substance dissolves D) Substance changes shape.

Answer:

The answer is C.

a. NH3 (Ammonia): In a 1.0L container of NH3 at Standard Temperature and Pressure (STP), intermolecular forces such as hydrogen bonding would be exerted.

b) 1.0L container of CHCl3 at STP, dipole-dipole interactions (along with London dispersion forces) would be present.

a. NH3 (Ammonia):

In a 1.0L container of NH3 at Standard Temperature and Pressure (STP), intermolecular forces such as hydrogen bonding would be exerted. Ammonia (NH3) molecules consist of one nitrogen atom bonded to three hydrogen atoms, forming a trigonal pyramidal shape.

Hydrogen bonding is a type of intermolecular force that occurs when a hydrogen atom is covalently bonded to an electronegative atom (in this case, nitrogen) and interacts with another electronegative atom (in this case, the nitrogen atom of a neighboring NH3 molecule).

b. CHCl3 (Chloroform):

In a 1.0L container of CHCl3 (chloroform) at STP, intermolecular forces such as dipole-dipole interactions would be exerted. Chloroform (CHCl3) molecules consist of one carbon atom bonded to three hydrogen atoms and one chlorine atom, forming a tetrahedral shape.

Dipole-dipole interactions arise due to the difference in electronegativity between chlorine and hydrogen atoms. The chlorine atom is more electronegative than hydrogen, resulting in a polar covalent bond.

While dipole-dipole interactions are present in CHCl3, it is worth noting that CHCl3 also exhibits London dispersion forces. These forces occur due to temporary fluctuations in electron distribution, creating temporary dipoles.

London dispersion forces are the weakest type of intermolecular force but still contribute to the overall intermolecular interactions in CHCl3.

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Answer:

C

Explanation:

Hydrogen has one electron in its outermost shell, while fluorine has seven electron in its outermost shell, hence both hydrogen and fluorine needs a single electron to complete its outermost shell. That's why there is a single bond between hydrogen and fluorine.

Both hydrogen and fluorine share one electron with each other for the completion of their outermost shell. So the correct option is C.

In chemistry, the interatomic linkage that can be formed between atoms of the same or different elements and is due to the sharing of an electron pair between two atoms is called a covalent bond.

The kind of bonding is the result of an electrostatic force of attraction of their nuclei for the same electrons so that they can complete their octet. When the bonded atoms have lower total energy than that of widely separated atoms, a covalent bond is formed m

The inorganic substances hydrogen, nitrogen, chlorine, water, and ammonia (H2, N2, Cl2, H2O, NH3) and also all the organic compounds are the molecules that have covalent bonding. In the case of structural representations of molecules, this type of bonding is indicated by solid lines that connect pairs of atoms.

Therefore the correct option is C.

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0.555 atm is the pressure of a fixed volume of a gas at 30.0C if it has a pressure of 1.11atm at 15C.

The ideal gas equation, pV = nRT, is an equation used to calculate either the pressure, volume, temperature or number of moles of a gas.

According to Ideal Gas Equation,

PV = nRT

Therefore, P ∝ T

P₁T₂ = P₂T₁

Given :

P₁ = ?

P₂ = 1.11 atm

T₁ = 30.0 C

T₂ = 15 C

Solving :

P₁ x 30 = 1.11 x 15

P₂ = 0.555 atm

Hence, 0.555 atm is the pressure of a fixed volume of a gas at 30.0C if it has a pressure of 1.11atm at 15C.

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Answer:

Nuclear fusion is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles (neutrons or protons).

Answer:

The answer is Satellite

Explanation:

ANSWER

The number of moles of Pb(SO4)2 is 1.5 moles

EXPLANATION

Given that;

The mass of Li2SO4 is 330g

Follow the steps below to find the moles of Pb(SO4)2

Step 1; Write the balanced equation of the reaction

Step 2; Find the number of moles of Li2SO4 using the below formula

Recall, that the molar mass of Li2SO4 is 109.94 g/mol

The number of moles of Li2SO4 is 3.00 moles

Step 3; Find the number of moles of Pb(SO4)2 using a stoichiometry ratio

In the above equation of the reaction, 1 mole Pb(SO4)2 reacts to give 2 moles LiSO4

Let the number of moles of Pb(SO4) be x

Therefore, the number of moles of Pb(SO4)2 is 1.5 moles

The following statements correctly describe ionization energy: "The ionization energy increases for the removal of each subsequent electron" and "The ionization energy describes the energy needed to add an electron to a neutral atom."

Ionization energy is the energy required to remove an electron from a neutral atom or ionize it. It is an important property that reflects the ease with which an atom loses electrons. Based on this concept, the ionization energy follows certain trends.

The statement "The ionization energy increases for the removal of each subsequent electron" is correct. As electrons are successively removed from an atom, the ionization energy generally increases because the remaining electrons experience greater electrostatic attraction from the positively charged nucleus.

Additionally, the statement "The ionization energy describes the energy needed to add an electron to a neutral atom" is also correct. Ionization energy can also refer to the energy required to add an electron to a neutral atom, forming a negatively charged ion.

The other statements, including "IE1 for a given element is always larger than IE2," "Ionization energy is always positive (i.e., endothermic)," "Ionization energy is always negative (i.e., exothermic)," "IE, for a given element is never larger than IE2," and "IE, for a given element is sometimes larger than IE2," are not correct descriptions of ionization energy.

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Answer:

5 000 000 (5 million atoms)

Explanation:

Let us assume that a vanadium atom has a spherical shape.

diameter of a sphere = 2 x radius of the sphere

Thus,

Radius of a vanadium atom = 130 pm

                                              = 130 x \(10^{-12}\) m

The diameter of a vanadium atom = 2 x radius

                                                         = 2 x 130 x \(10^{-12}\)

                                               = 260 x \(10^{-12}\) m

Given a distance of 1.30 mm = 1.30 x \(10^{-3}\) m,

The number of vanadium atoms required to span the distance = \(\frac{1.3*10^{-3} }{260*10^{-12} }\)

                                                  = 5000000

Therefore, the number of vanadium atom that would span a distance of 1.30 mm is 5 million.

The mass of Hg in the sample is 17.1g.

One of the fundamental quantities in physics and the most fundamental feature of matter is mass. The quantity of matter in a body is referred to as its mass. The kilogram, the standard international unit of mass (kg). You can write the mass formula as follows:

Mass = Density × Volume

The water weighs 1400 g. And one night later, we grew by one. Therefore, multiplying X 12.2 by 1400 multiplied by a million. We therefore possess 0.01708 grammes of mercury. When converted to milligrams, this amount equals 17.1 milligrams of mercury.

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15 grams of CaF2 is equal to 0.844 moles. Therefore, there are 0.844 moles of CaF2, or 6.752 formula units of CaF2.

Answer:

The bonding and molecular polarity in a molecule of CI2 is best described as palar / polar

An equimolar mixture of two optical isomers is called a racemic mixture or a racemate.

Both enantiomers or optical isomers, are equally present in a racemic mixture. Enantiomers are molecules that share the same connectivity and chemical formula but differ in how they are arranged in three dimensions, creating mirror-image structures. The polarised light plane can rotate in opposing orientations for each enantiomer.

However, when they are combined in equal amounts, their optical rotations cancel one another out, resulting in a racemic mixture that is net optically inactive. Racemic mixes, which differ from their individual enantiomers in a variety of ways, are frequently seen in chemical and biological systems.

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Answer:

acceleration(a)=2m/s²

Explanation:

initial velocity(u)=0m/s

final velocity (v)=20m/s

time taken (t)=10sec

now

v=u+at

20=0+a*10

a=2m/s²

Answer:

84400cg

Explanation:

100000 cg in 1kg

100000(8.44)=84400cg

According to the website that I use to figure out things about science or chemistry and that stuff... The answer is 3.5 L KBr x 1.7 mol KBr solute / 1 L KBr solution x 1 mol Cl2 / 2 mol KBr x 70.9 g Cl2 / 1 mol Cl2 = 211 g Cl2.

Answer:

Decay. Plutonium-242 primarily decays into uranium-238 via alpha decay, before continuing along the uranium series.

Explanation:

please mark as brainlist

Answer:

Pluto is farthest from the sun and hence it receives extremely low energy of sun. The surface temperature of Pluto is about -240 !!!

Answer:

Water is a remarkable substance, and its unique properties are largely due to the presence of polar covalent bonds and hydrogen bonds in its structure. These characteristics play a crucial role in the physical and chemical properties of water, making it essential for life as we know it.

Explanation:

The polar covalent bonds in water arise from the unequal sharing of electrons between oxygen and hydrogen atoms. This results in the oxygen atom having a partial negative charge (δ-) and the hydrogen atoms having partial positive charges (δ+). These charges create polarity within the water molecule, leading to the formation of hydrogen bonds.

Hydrogen bonds occur when the partially positive hydrogen atom of one water molecule is attracted to the partially negative oxygen atom of another water molecule. These hydrogen bonds are relatively weak individually, but when present in large numbers, they contribute to the cohesion, surface tension, and high boiling point of water.

The importance of these bonds is manifold. The cohesion between water molecules due to hydrogen bonding enables water to form droplets, have a high surface tension, and flow freely, facilitating transport within organisms and in the environment. Additionally, hydrogen bonding leads to the high specific heat capacity and heat of vaporization of water, making it an effective regulator of temperature in living organisms and ensuring stable environmental conditions.

Furthermore, hydrogen bonds play a crucial role in the unique properties of water as a solvent. The polar nature of water allows it to dissolve a wide range of substances, including ionic compounds and polar molecules, facilitating various biological processes such as nutrient transport and chemical reactions in cells.