Question

question 43 (0.0862 points)
how many moles of lithium nitrate are theoretically produced if we start with 3.1 moles of ca(no3)2 and 2.4 moles of li3po4?
give just the number with the correct significant figures.
reaction: 3ca(no3)2 + 2li3po4 → 6lino3 + ca3(po4)2

question 44 (0.0862 points)
consider a 1.6 × 10⁻³ m solution of hno3. which of the following statements is not true?

○ the solution is acidic
○ the solution could neutralize a base
○ the solution could dissolve many metals

Explanation:

Question 43

Step1: Determine Limiting Reactant

First, find the moles of \( \text{LiNO}_3 \) produced from each reactant.
From \( \text{Ca(NO}_3\text{)}_2 \):
Mole ratio \( \frac{6\ \text{mol LiNO}_3}{3\ \text{mol Ca(NO}_3\text{)}_2} \).
Moles of \( \text{LiNO}_3 = 3.1\ \text{mol Ca(NO}_3\text{)}_2 \times \frac{6}{3} = 6.2\ \text{mol} \).

From \( \text{Li}_3\text{PO}_4 \):
Mole ratio \( \frac{6\ \text{mol LiNO}_3}{2\ \text{mol Li}_3\text{PO}_4} \).
Moles of \( \text{LiNO}_3 = 2.4\ \text{mol Li}_3\text{PO}_4 \times \frac{6}{2} = 7.2\ \text{mol} \).

The smaller value (6.2) comes from \( \text{Ca(NO}_3\text{)}_2 \), so it is the limiting reactant.

Step2: Check Significant Figures

The given moles (3.1, 2.4) have two significant figures. The result from the limiting reactant (6.2) also has two significant figures, which matches.

• \( \text{HNO}_3 \) is a strong acid, so the solution is acidic (true).
• Acids neutralize bases (true).
• Dilute \( \text{HNO}_3 \) (like \( 1.6 \times 10^{-3}\ \text{M} \)) does not dissolve many metals (unlike concentrated \( \text{HNO}_3 \) or strong acids like \( \text{HCl} \)/\( \text{H}_2\text{SO}_4 \) for some metals). The "dissolve many metals" statement is NOT true.

Answer:

6.2

Question 44