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4 years ago

Which statement is true of a chemical change?

2 answers:

5 0

The appropriate answer is a. it involves a change in the molecular structure of the substance. A change in phase or state is referred to as a physical change. For example...liquid water freezing is a physical change because the state changes but solid water is still H20. Separating water into its constituent atoms, hydrogen and oxygen is a chemical change because the molecular structure of water is now non existent.

tatiyna4 years ago

4 0

The answer is c. There wouldnt be a process or a change to it

You might be interested in

Which change of phase is endothermic chem test.

nikdorinn [45]

Answer:

Melting is an example of an endothermic change.

Explanation:

This is because the system absorbs (heat) energy from the surroundings to increase its temperature.

5 0

2 years ago

What volume of 1.75 M hydrochloric acid (HCl aq) must be diluted with water to prepare 0.500 L of 0.250 M hydrochloric acid?

Airida [17]

Answer:

$V_1=0.0714L$

Explanation:

Hello there!

In this case, since we need to dilute the 1.75-M HCl, and the total number of moles remain unchanged, we can write:

$n_1=n_2$

And in terms of volume and concentration:

$C_1V_1=C_2V_2$

Thus, we can solve for the volume of the concentrated HCl as shown below:

$V_1=\frac{C_2V_2}{C_1}$

Therefore, we plug in the data to get:

$V_1=\frac{0.250M*0.500L}{1.75 M}\\\\V_1=0.0714L$

Best regards!

7 0

3 years ago

Match the effects on the concentration of SO3 gas when the following changes occur after initial equilibrium has been establishe

mestny [16]

The effects on the concentration of SO3 gas when the following changes occur after initial equilibrium has been established in this system (N.C. = no change) by adding a catalyst.

2SO2(g) + O2(g) 2SO3(g) + 46.8 kcal

So that even though there is an addition of catalyst, no change in reactants or products has occurred because catalyst only provides a faster pathway for the reaction to occur.

3 0

4 years ago

Read 2 more answers

What are the spectator ions in this equation?

dangina [55]

The given question is incomplete. The complete question is :

What is the net ionic equation for the following reaction?

$H_2CrO_4+Ba(OH)_2$

Answer : The spectator ions are $Ba^{2+}$ and $CrO_4^{2-}$

Explanation:

Neutralization is a chemical reaction in which an acid and a base reacts to form salt and water.

Spectator ions are defined as the ions which does not get involved in a chemical equation or they are ions which are found on both the sides of the chemical reaction present in ionic form.

The given chemical equation is:

$2H^+(aq)+CrO_4^{2-}(aq)+Ba^{2+}(aq)+2OH^-(aq)\rightarrow Ba^{2+}(aq)++CrO_4^{2-}(aq)+H_2O(l)$

The ions which are present on both the sides of the equation are barium and chromate ions. and hence are not involved in net ionic equation.

Hence, the net ionic equation is $H^++OH^-\rightarrow H_2O$

6 0

3 years ago

How many phases of water are represented in the phase diagram? *

Arada [10]

Answer: All three phases of water coexist in equilibrium.

Explanation:

8 0

4 years ago