Which substance cannot be decomposed by a chemical change?

A pair of students found the temperature of 100. g of water to be 26.5°C. They then dissolved 8.89 g of AgNO3 in the water. When

bekas [8.4K]

Explanation:

Initial temperature of the water = $T_i=26.5^oC$

Final temperature of the water = $T_f=23.7^oC$

a) Change in temperature of the water,ΔT = $T_f-T_i$

$\Delta T=23.7^oC-26.5^oC=-2.8^oC$

Change in temperature of the water,ΔT is -2.8°°C.

b) Endothermic reaction : Reaction in which heat absorbed and the temperature if the surrounding is decreased.

Exothermic reaction : Reaction in which heat released and the temperature if the surrounding is increased.

On dissolving silver nitrate in water the temperature of the water decreased 2.8 degree Celsius which means that energy water was absorbed by solid silver nitrate to get dissolve in water. Hence, endothermic reaction.

(f) Mass of silver nitrate = 8.89 g

Moles of silver nitrate = $\frac{8.89 g}{170 g/mol}=0.05229 mol$

$AgNO_3(aq)\rightarrow Ag^+(aq)+NO_3^-(aq)$

1 mole of silver nitrate gives 1 mole of silver ion i.e. cation.

Then 0.05229 moles of silver nitrate will give:

$\frac{1}{1}\times 0.05229 mol=0.05229 mol$ silver ions.

0.05229 moles of cations are produced.

1 mole of silver nitrate gives 1 mole of nitrate ion i.e. anion .

Then 0.05229 moles of silver nitrate will give:

$\frac{1}{1}\times 0.05229 mol=0.05229 mol$ nitrate ions.

0.05229 moles of anion are produced.

5 0

3 years ago

The gram formula mass of a compound is 48 grams. The mass of 1.0 moles of this compound is

ehidna [41]

The gram formula mass is Molar mass. The mass of 1.0 moles is :
3) 48.0 g

3 0

3 years ago

You have a glass of liquid and combine it with a mysterious solid and notice that over time the color changes. this questions ha

Juliette [100K]

1. This can be due to the dissolving of the solid in liquid and form a solution.

Dissolving is a physical property because dissolving doesn't form new substances and the chemical composition of the solid is not changed.

The color building up over the time can be due to the rate of dissolving of the solid and amount of particles have been dissolved.

Example:

Dissolving of CuSO₄ solid in water.
This develops a blue color.

2. This can be due to the chemical reaction between the solid and liquid.

Chemical reaction is a chemical property because from reacting substances new substances can be formed which the chemical formula is different from initial substances.

The color building up over the time can be due to the rate of the reaction and the amount of reactants.

Example:

The reaction between calcium metal with water.
The color of Ca(OH)₂ is white color.
Reaction is

Ca(s) + 2H₂O(l) → Ca(OH)₂(aq) + H₂(g)

5 0

3 years ago

6th grade science . :((

Nadusha1986 [10]

Answer:

C- private

Explanation:

This event seems to be exclusive. That is why it is private.

3 0

3 years ago

Which of the following diagrams represents a single<br> replacement reaction?

kari74 [83]

Answer:

It's a, trust me I'm very good with chemistry

3 0

2 years ago