Which of the following compounds will form a solution if exposed to air?

Ifa4sure

13 years ago

Calcium chloride is correct because it will turn to solution when expose to air {deliquescence} while NaNo3 is wrong because it is hygroscopy which merely become sticky

israelmichael1

1 year ago

The correct answer is:

**D. CaCl₂ (Calcium chloride)**

### Explanation:
A compound that **forms a solution when exposed to air** is called **deliquescent**. Deliquescent substances absorb moisture from the air until they dissolve in the absorbed water, forming a solution.

- **Calcium chloride (CaCl₂)** is **highly deliquescent**, meaning it absorbs so much water from the air that it dissolves in it. That’s why it's often used as a **drying agent (desiccant)**.

### Why Other Options Are Incorrect:
- **A. Na₂CO₃·10H₂O (Sodium carbonate decahydrate)** → This is **efflorescent**, meaning it **loses water** to the air, not absorbs it.
- **B. NaNO₃ (Sodium nitrate)** → While it is **highly soluble**, it is **not deliquescent**.
- **C. CuSO₄ (Copper(II) sulfate)** → This does **not absorb enough moisture** to form a solution. However, the hydrated form (**CuSO₄·5H₂O**) can lose water and turn white when exposed to air (efflorescence).
- **E. Na₂SO₄·10H₂O (Sodium sulfate decahydrate)** → Like **Na₂CO₃·10H₂O**, this is also **efflorescent**, meaning it **loses water instead of absorbing it**.

### Conclusion:
Since **CaCl₂** absorbs moisture and eventually dissolves in it, the correct answer is:
**D. CaCl₂**.

Aderayo77

9 years ago

Calcium chloride is deliquescent

amaechi unya

13 years ago

yes bcus 02 is not in de comp cacl2

Ifa4sure

13 years ago

Calcium chloride will turn to solution when expose to air {deliquescence} while NaNo3 is hygroscopy which merely become sticky

Segzycl23

4 months ago

yes

Emmexab

1 year ago

can someone explain further for me
pllss

jaystar45a

10 years ago

Hi

Gods Gift

13 years ago

Why do you say Nacl?

Mr.Man

13 years ago

Datz correct

Greatfred

13 years ago

Ya .d ans is cacl .cos it wil react with O2 to form CaO nd liberating chlorine gas.nd u knw ca wil displace cl nd O2 in d reactivity series

Emmanuelwaibode

7 years ago

Explanation are necessary,but are not given in most questions,why

thobhiara

8 years ago

yea,calcium chloride is deliquenscence.Therefore,option D is correct....mind u,sodium trioxonitrate(v) is hygroscopy

kasielu

12 years ago

cacl & NaNO3 are hygroscopic salts; but CuSo4 is deliquescent, cos wen react with H2o forms CuO & H2SO4,so C is d answer.

Oshobu

9 years ago

CaCl2 is hygroscopic because it used to absorb water from chemical reaction while CuSO4 is deliquescent because it react with water to form Anhydrous Copper Sulphate (e.g CuSO4.10H2O). So the correct answer is D