Which of the following statements is true ?

Options

A. All metal nitrates are soluble in `H_(2)O`
B. All metal nitrates are insoluble in water
C. solubility depends upon temperature
D. either A or B

Explanation

To determine which statement is true regarding metal nitrates and their solubility in water, let's analyze the statements step by step.

### Step 1: Understand Metal Nitrates
Metal nitrates are formed when metals react with nitric acid. They typically have the general formula M(NO₃)₂, where M represents the metal.

**Hint:** Recall the reaction of metals with acids and the general formula of metal nitrates.

### Step 2: Solubility of Metal Nitrates
Most metal nitrates are ionic compounds. Ionic compounds tend to dissolve in water because the positive and negative ions are attracted to the polar water molecules, allowing them to separate and disperse in solution.

**Hint:** Think about the nature of ionic compounds and how they interact with water.

### Step 3: Evaluate the Statements
1. **Statement A:** "All metal nitrates are soluble in water."
- This statement is generally true. Most metal nitrates are soluble in water, making this statement correct.

2. **Statement B:** "All metal nitrates are insoluble in water."
- This statement is incorrect because, as established, most metal nitrates are soluble.

3. **Statement C:** "Solubility depends on temperature."
- While solubility can depend on temperature for some substances, the statement implies that all metal nitrates have variable solubility based on temperature, which is misleading. Most metal nitrates are soluble regardless of temperature, making this statement incorrect.

**Hint:** Compare the statements to what you know about the solubility of ionic compounds.

### Step 4: Conclusion
Based on the analysis:
- The correct statement is **Statement A**: "All metal nitrates are soluble in water."

**Final Answer:** Statement A is true.