Here you go! There are 0.9307 moles in 123.0 g of the compound. I solved this by using a fence post method. I calculated the number of grams in one mol of (NH4)2 SO4 and got 132.16.
I did this by finding the atomic mass of each element on the periodic table (my work is in the color blue for this step)
After that, i divided the given mass by the mass of one mol of the compound.
The answer is 0.9307 moles!! I hope this helped you! :))
At STP, pure ethanol has density 0.789g/mL. 25 mL will have mass 25 (mL) * 0.789 (g/mL)=19.725 g. Round this to 19.7g for three significant figures.
(not fully sure if this is correct)
Answer: 1.55 Jg°C
Explanation:
The quantity of Heat Energy (Q) required to heat a substance depends on its Mass (M), specific heat capacity (C) and change in temperature (Φ)
Thus, Q = MCΦ
Since,
Q = 943 joules
Mass of oil = 10g
C = ? (let unknown value be Z)
Φ = (Final temperature - Initial temperature)
= 89°C - 28°C = 61°C
Then, Q = MCΦ
943 J = 10g x Z x 61°C
943J = 610g°C x Z
Z = (943J / 610g°C)
Z = 1.55 Jg°C
Thus, the specific heat of the oil is 1.55 Jg°C