Nickel is a pure substance
Rust is also a pure substance
Answer:
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Explanation:
You don't give the reaction, but we can get by just by balancing atoms of Na.
We know we will need the partially balanced equation with masses, moles, and molar masses, so let’s gather all the information in one place.
M_r: 142.04
2NaOH + … ⟶ Na₂SO₄ + …
n/mol: 0.75
1. Use the molar ratio of Na₂SO₄ to NaOH to calculate the moles of NaF.
Moles of Na₂SO₄ = 0.75 mol NaOH × (1 mol Na₂SO₄/2 mol NaOH
= 0.375 mol Na₂SO₄
2. Use the molar mass of Na₂SO₄ to calculate the mass of Na₂SO₄.
Mass of Na₂SO₄ = 0.375 mol Na₂SO₄ × (142.04 g Na₂SO₄/1 mol Na₂SO₄) = 53 g Na₂SO₄
The reaction produces
of Na₂SO₄.
Answer:
The answer is B
B) gravitational potential energy only
<h3>
Answer: <em>
pH=2.25 </em></h3>
Explanation:
monochloroacetic acid also means: chloroacetic acid
pKa of monochloroacetic acid= 1.4 x 10^-3 (I believe this should have been given in the problem or perhaps in the textbook)
Formula: pH= pKa + log ( some number in M)
pH= -log (1.4 x 10^-3) + log (0.25M)= 2.85 + -0.602= 2.25
pH= 2.25
Elements in the same group have similar properties