<span>The mass of one mole of sodium bicarbonate (aka NaHCO3) is equal to 1 * 22.99g/mol + 1 * 1.00g/mol + 1 * 12.01g/mol + 3 * 16.00g/mol = 83.91g/mol. From this, we can convert 4.2g of NaHCO3 to moles by dividing by 83.91g/mol, to get 0.050 moles of sodium bicarbonate.</span>
When the enthalpy change of the reaction is positive, the reaction is exothermic.
B: a liquid becomes a gas Let me know if it’s right or wrong
Answer:
m = 17
Explanation:
From the question we were given that
Triangle WZY is bisected by ZX; ZW = ZY
∠YXZ = (6m – 12)°
Based on the characteristics of the triangle, we see that triangle WYZ is an isosceles triangle (that is, triangle WXZ is equal to triangle YXZ)
<YXZ = <WXZ = 90°
Using ∠YXZ = (6m – 12)°
We have:
(6m – 12)° = 90°
6m = 90 + 12 ⇒ 6m = 102
m = 102 ÷ 6 = 17
m = <u>17</u>
<u>We therefore see that m is equal to 17</u>