Answer: Mass is 2,37 kg
Explanation: Weight G = mg, and g = 9.81 m/s² on Earth.
m = W/g = 23.2 N / 9.81 m/s²
Answer:
1116 g.
Explanation:
The balanced equation for the reaction is given below:
4Na + O₂ —> 2Na₂O
From the balanced equation above,
1 mole of O₂ reacted to produce 2 moles of Na₂O.
Next, we shall determine the theoretical yield of Na₂O. This can be obtained as follow:
From the balanced equation above,
1 mole of O₂ reacted to produce 2 moles of Na₂O.
Therefore, 9 moles of O₂ will react to produce = 9 × 2 = 18 moles of Na₂O.
Finally, we shall determine the mass in 18 moles of Na₂O. This can be obtained as follow:
Mole of Na₂O = 18 moles
Molar mass of Na₂O = (23×2) + 16
= 46 + 16
= 62 g/mol
Mass of Na₂O =?
Mass = mole × molar mass
Mass of Na₂O = 18 × 62
Mass of Na₂O = 1116 g
Thus, the theoretical yield of Na₂O is 1116 g.
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>
