1. You can use Avogadro’s number, 6.022x10^23 atoms/mole, to answer this one.
(3.311x10^24/6.022x10^23) = 5.498 moles of substance
2. H2O has a formula weight approximately equal to 18 grams. Dividing the given amount by the formula weight of water will tell us the number of moles present.
126/18 = 7 moles H2O
NaHCO3 is the answer for the query
Answer:
1185.0 J.
Explanation:
- The amount of heat needed to accomplish this process can be calculated using the formula:
<em>Q = m.C.ΔT</em>, where,
Q is the amount of heat needed,
m is the mass of the copper <em>(m = 47.35 g)</em>,
C is the specific heat of Cu<em> (C = 0.385 J/g.°C)</em>,
ΔT is the temperature difference (the final temperature - the initial temperature <em>(ΔT = 85.0 - 20.0 = 65.0 °C)</em>.
<em>∴ The amount of heat needed Q = m.C.ΔT </em>= (47.35 g) (0.385 J/g.°C) (65.0 °C) = 1184.933 J ≅ 1185.0 J.
Pretty sure the answer is C
