Which of the following is evidence of a chemical change?

Chemistry

2 answers:

krek1111 [17]3 years ago

5 0

<span>the formation of a gas
</span>

larisa86 [58]3 years ago

5 0

Answer:

the formation of a gas

Explanation:

The chemical change is one in which some chemical reaction occur.

a) Phase change : it is simply change of one state of matter to another.

For example conversion of ice to liquid water, where there is no change in chemical composition of water and only the physical state is changing.

b) formation of gas: it is possible when some substance breaks into some other components or some substance reacts with other. This is definitely a chemical change as bonds will break and may be new bonds will form.

For example decomposition of calcium carbonate gives carbon dioxide (a gas) and calcium oxide.

c) mass change: it could be due to evaporation of water from a substance. Which must be a physical change.

d) surface area: change in surface is area must be due to change in state or physical modifications in state of a substance.

You might be interested in

How much does the mass of 12.65-g sample of copper(II) nitrate hexahydrate decrease when heated?

garik1379 [7]

There is 103 percent of water in hydrate

4 0

3 years ago

The ____________________ is done first so that you know how you want to go about your ____________________.

N76 [4]

We need a photoooooooo

8 0

3 years ago

Read 2 more answers

The Cabbage Indicator

Masja [62]

.A solution that serves as a pH indicator may be made using red cabbage, which is frequently available in homes. In essence, the color of the cabbage depends on the acidity of the solution and a pigment molecule called flavin or anthocyanin.

To determine whether a material is an acid or a base, red cabbage indicator is a purple-colored solution

Vinegar is an acid and its pH value is less than 7 and hence

Red color is produced

Baking soda is base and its pH value is greater than 7 and between 8-9

and the color produced is sky blue

Bleach is the green which is also a basic and because the pH value is 10-11

Householder cleaner is having pH 11-13 which is basic and hence the yellow is the color of household cleaner .

A basic solution goes away from being basic and toward the center of the pH scale when an acid is introduced. The base is "neutralized" in this manner.