Answer:
Distance
Explanation:
The light-year is a measure of distance, not time. It is the total distance that a beam of light, moving in a straight line, travels in one year.
What is the percent composition by mass of oxygen in magnesium oxide, MgO?
Answer: 39.7 percent
Answer:
1 x 10⁻¹¹ M
Explanation:
<u>(Step 1)</u>
Determine the pH.
pH = -log[H⁺]
pH = -log[1 x 10⁻³ M]
pH = 3
<u>(Step 2)</u>
Determine the pOH.
pH + pOH = 14
3 + pOH = 14
pOH = 11
<u>(Step 3)</u>
Determine the hydroxide (OH⁻) concentration.
[OH⁻] = 10^-pOH
[OH⁻] = 10⁻¹¹
[OH⁻] = 1 x 10⁻¹¹ M
