<span>1.11 g/cm³
Hope this helps! </span>
Answer:
5.0 × 10²⁴ molecules
Explanation:
Step 1: Write the balanced double displacement reaction
2 NaOH + CuSO₄ ⇒ Na₂SO₄ + Cu(OH)₂
Step 2: Calculate the moles corresponding to 5.0 × 10²⁴ molecules of Na₂SO₄
We will use Avogadro's number: there are 6.02 × 10²³ molecules in 1 mole of molecules.
5.0 × 10²⁴ molecule × 1 mol/6.02 × 10²³ molecule = 8.3 mol
Step 3: Calculate the moles of CuSO₄ required to produce 8.3 moles of Na₂SO₄
The molar ratio of CuSO₄ to Na₂SO₄ is 1:1. The moles of CuSO₄ required are 1/1 × 8.3 mol = 8.3 mol.
Step 4: Calculate the molecules corresponding to 8.3 moles of CuSO₄
We will use Avogadro's number.
8.3 mol × 6.02 × 10²³ molecule/1 mol = 5.0 × 10²⁴ molecule
Answer:
b) 2.0 mol
Explanation:
Given data:
Number of moles of Ca needed = ?
Number of moles of water present = 4.0 mol
Solution:
Chemical equation:
Ca + 2H₂O → Ca(OH)₂ + H₂
now we will compare the moles of Ca and H₂O .
H₂O : Ca
2 : 1
4.0 : 1/2×4.0 = 2.0 mol
Thus, 2 moles of Ca are needed.
The answer is A it's a basic because once you add another substance to a neutral it either becomes acidic or basic. this one becomes basic because the hydroxide ion concentrate increased.