The answer is D I hope this helps you !
<u>We are given:</u>
Mass of Na added = 4.35 grams
Mass of water = 105 grams
<u>Mass Percent of Na:</u>
Total mass of the solution = mass of solute + mass of solvent
Total mass of the solution = 4.35 + 105 = 109.35 grams
Mass percent of solute = (mass of solute / mass of solution) * 100
Mass percent of Solute = (4.35 / 109.35) * 100
Mass percent = 3.978 %
Answer:
2.5 × 10⁻⁵ M H₃O⁺ and 4.0 × 10⁻¹⁰ M OH⁻.
Explanation:
<em>∵ pH = - log[H₃O⁺]</em>
∴ 4.6 = - log[H₃O⁺].
∴ log[H₃O⁺] = - 4.6.
∴ [H₃O⁺] = 2.51 x 10⁻⁵.
∵ [H₃O⁺][OH⁻] = 10⁻¹⁴.
[H₃O⁺] = 2.51 x 10⁻⁵ M.
∴ [OH⁻] = 10⁻¹⁴/[H₃O⁺] = 10⁻¹⁴/(2.51 x 10⁻⁵ M) = 3.98 × 10⁻¹⁰ M ≅ 4.0 × 10⁻¹⁰ M.
<em>So, the right choice is: 2.5 × 10⁻⁵ M H₃O⁺ and 4.0 × 10⁻¹⁰ M OH⁻.</em>
✡ Answer: 1.23*10^2 ✡
- - Add a decimal at the end (to the right) and count till you get to the first number.
So now you have 1.23
- - Now you always want to times it by 10 to the power of how many times you moved it over, in this case, 2
Final answer: 1.23*10^2
✡Hope this helps✡
