how many atoms are in each compound ?

Answer:

The dissolution of sodium chloride involves three steps. During the process energy changes occur in:

1. breaking apart the hydrogen bonds between water molecules,

2. breaking apart the electrostatic bonds between sodium and chloride ions, and

3. when bonds are formed between water molecules and aqueous ions in solution.

Since the energy used to break apart the hydrogen bonds between water molecules and the energy used to break apart the electrostatic bonds between sodium and chloride ions, is greater than the energy released when bonds are formed between water molecules and aqueous ions in solution, the dissolution of sodium chloride is endothermic.

Explanation:

The heat of solution or enthalpy of solution/dissolution, is the enthalpy change that occurs with the dissolution of a solute in a solvent at constant pressure, resulting in infinite dilution. Its unit is kJ/mol for reactions taking place under standard conditions (298.15 K and 1 atm).

The process of dissolution occurs in three energy-dependent steps:  

1. The breaking of bonds within the solute. For example, electrostatic forces of attraction between two oppositely-charged ions. This process is endothermic.

2. The endothermic process of breaking of intermolecular forces within the solvent, e.g. hydrogen bonds in water.

3. The exothermic process of the formation of new solute-solvent bonds in solution.

The sum of the energies involved in these three steps gives the enthalpy of dissolution of a solute. The overall process of dissolution can either endothermic or exothermic depending on the amount of energy used or released in breaking and making bonds. If more energy is released in making than is used in breaking bonds, it is exothermic.  However, if more energy is used in breaking bonds than is released in making bonds, dissolution is then endothermic.

For example, considering the dissolution of sodium chloride. During the process the energy used to break apart the hydrogen bonds between water molecules and the energy used to break apart the electrostatic bonds between sodium and chloride ions, is greater than the energy released when bonds are formed between water molecules and aqueous ions in solution. Therefore, the dissolution of sodium chloride is endothermic.

Answer:I can’t see the question

Explanation:

Answer:

On contact with ice, calcium chloride forms brine rapidly, which lowers the freezing point of water and melts snow and ice quickly. Calcium chloride forms brine faster than other ice melters because its hygroscopic properties actually cause it to attract moisture from its surroundings

Explanation:

HOPE IT WILL HELP YOU

Answer:

210 microliters of drug are needed to fill the capsule

Explanation:

As given in the question

1 liter is equal to [tex]10^6[/tex] micro liters

Volume of Capsule [tex]= 210[/tex] cubic millimeter

1 cubic millimeter  [tex]= 10^{-3}[/tex] cubic meter

1 cubic meter [tex]= 10^3[/tex] liters

1 micro liter [tex]= 10^{-6}[/tex] micro liters

Converting [tex]210[/tex] cubic millimeter to micro liter

[tex]= 210 * (10^{-3})^3 * 10^3 \\= 210 * 10^{-6}\\= 210[/tex]micro liters

Answer:

The sign of change of heat of solution is positive

Explanation:

The dissolution of AgNO3 in water is represented by the equation;

AgNO3(s) --------> Ag^+(aq) + NO3^-(aq)

We can see from the question that as the temperature was increased from 10° to 20°C the solubility of the solute increased from  170g to 222g per 100g of H2O.

This implies that the solubility of the solute increases with increase in temperature.

If a reaction moves in the forward direction when the temperature is increased, then the reaction is endothermic. If the reaction is endothermic, the sign of change of heat of solution is positive.

Answer:

Element with 6s subshell

Explanation:

Reactivity of an element depends on the electronic configuration and position of element in the periodic table as reactivity increases as we go down the periodic table.

This is so because number of shell increases as move down the periodic table and the last electron is further away from the nucleus.

Element with 6s subshell is the largest among 3s and 4s subshell and has more number of shells so it will react more than 3s and 4s subshell.

Hence, the correct answer is "Element with 6s subshell".

Answer:

The designs ensure that the experimental.

Explanation:

Scientific research refers to the-fact finding inquiry to answer the questions related to natural processes. A hypothesis is a situation or an assumption that needs to be proved by applying scientific produces. Experimental design refers to the methodology, which is applied to conduct research.

The designs ensure that the experimental data support the hypothesis is the true statement regarding experimental designs that are used in scientific research because an experimental design should be concerned with the fact that it is relevant or appropriate to prove a hypothesis.

Answer:

its c. the designs follow a general method that is familiar to all scientists

Explanation:

Answer:

Wal-mart XDDDDD

Explanation:

Answer:

Potential energy I believe

Explanation:

Answer:

false

Explanation:

earth is larger than mars so it has more gravity

Answer: false

Explanation:

Answer:

36gNb

Explanation:

0.39 mol Nb*92.91g Nb/1 mol Nb=36 g Nb

Answer:

As(OH)3 or AsH3O3

Explanation:

Answer:c

Explanation:

Answer:

This is a typical stoichiometry question.To answer this question you want to get a relationship between

N

a

2

O and NaOH.

So you can get a relationship between the moles of

N

a

2

O

and moles of NaOH by the concept of stoichiometry.

N

a

2

O +

H

2

O ----------------> 2 NaOH.

According to above balanced equation we can have the stoichiometry relationship between

N

a

2

O and NaOH. as 1:2

It means 1 moles of

N

a

2

O is required to react with one mol of

H

2

O to produce 2 moles of NaOH.

in terms of mass 1 mole of

N

a

2

O has mass 62 g on reaction with water produces 2 moles of NaOH or 80 g of NaOH.

62 g of

N

a

2

O produces 80 g of NaOH.

1g of NaOH is produced from 62/80 g of

N

a

2

O

1.6 x

10

2

g of NaOH will require 62 x 1.6 x

10

2

g / 80 of

N

a

2

O

124g of

N

a

2

O.

Explanation:

Answer:

KCl

Explanation:

hope this is correct and helps i did this last year in chem :)

[tex]\mathrm{KCl}[/tex]

Answer:

Cu3PO4

Explanation:

There are two types of chemical compound one is covalent compound and other is ionic compound, covalent compound formed by sharing of electron and ionic compound formed by complete transfer of electron. Therefore, Cu[tex]_3[/tex]PO[tex]_4[/tex] is the formula for copper(I) phosphate(v).

Chemical Compound is a combination of molecule, Molecule forms by combination of element and element forms by combination of atoms in fixed proportion.

An ionic compound is a metal and nonmetal combined compound.  Ionic compound are very hard. They have high melting and boiling point because of strong ion bond. Cu[tex]_3[/tex]PO[tex]_4[/tex] is the formula for copper(I) phosphate(v). Cu[tex]_3[/tex]PO[tex]_4[/tex] is an ionic compound with cation Cu⁺¹ and anion as PO₄³⁻.

Therefore, Cu[tex]_3[/tex]PO[tex]_4[/tex] is the formula for copper(I) phosphate(v).

To learn more about chemical compound, here:

brainly.com/question/26487468

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Answer:

ok

Explanation:

Answer:

it should be the second one :)

Explanation:

Answer:

because atomic number are numbers of protons

Explanation:

Specific heat capacity of gold (S)

= 0.126 J /kg°C

mass (m) = 350 g = 0.35 kg

difference in temperature (dt)

= 88.5°C - 24.6°C

= 63.9° C

Now

Energy released (Q)

= m*s*dt

= 0.35 * 0.126 * 63.9

= 2.81799 Joule

Hope it will help :)

10.6 mol NO

Math

Pre-Algebra

Order of Operations: BPEMDAS

Chemistry

Stoichiometry

Step 1: Define

[RxN - Balanced] 4NH₃ + 5O₂ → 4NO + 6H₂O

[Given] 13.2 mol O₂

Step 2: Identify Conversions

[RxN] 5 mol O₂ → 4 mol NO

Step 3: Stoich

Step 4: Check

Follow sig fig rules and round. We are given 3 sig figs.

10.56 mol NO ≈ 10.6 mol NO

N -3

Ba +2

Sr +2

F -1

I -1

Ca +2

Mg +2

S -2

S -2

Al +3

//

Ba3N2

SrF2

CaI2

MgS

Al2S3

//

I don't really understand 2.

Answer:

dissolving is classified as a physical change because it can be reversed back to its original form

explanation:

Dissolving is an example of a reversible change. For example, when salt is mixed with water it disappears because it dissolves in the water to make salty water. But we can get the salt can back again by boiling off the water. That leaves the salt behind.

Answer:

The usual cause of sea breeze is the difference in specific heat capacity between land and water Land heats and cools more quickly than water. What is the cause of a sea breeze? The air over the land is warmed and rises, to a greater temperature than that over the sea.

Explanation:

Your answer is C ! <3

The difference in specific heat capacity between land and water is the cause of sea breeze.

land and ocean heat up at different rates, sea breezes often occur during hot, summer days. The land surface warms up more quickly than the water surface during the day. As a result, the air above land is warmer than that over water.

Just to refresh your memory, warmer air is lighter than cooler air. Warm air rises as a result. As a result, the warmer air above the ground is rising. The cooler air above the water is moving across the surface of the land to replace the rising heated air as it rises over the land.

This is the sea breeze, which is seen at the top of the next picture. The land breeze that happens is seen at the bottom of the following picture.

Therefore, The difference in specific heat capacity between land and water is the cause of sea breeze.

To learn more about sea breeze, refer to the link:

https://brainly.com/question/13015619

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Molecular formula

hope that helps^^

Answer:

8 .....................