Answer:
97 000 g Na
Explanation:
The absortion (or liberation) of energy in form of heat is expressed by:
q=m*Cp*ΔT
The information we have:
q=1.30MJ= 1.30*10^6 J
ΔT = 10.0°C = 10.0 K (ΔT is the same in °C than in K)
Cp=30.8 J/(K mol Na)
If you notice, the Cp in the question is in relation with mol of Na. Before using the q equation, we can find the Cp in relation to the grams of Na.
To do so, we use the molar mass of Na= 22.99g/mol
Now, we are able to solve for m:
=97 000 g Na
Answer:
2.64%
Explanation:
mass percent = (grams of solute / grams of solution) x 100
mass percent = (2.4 / 91) × 100
mass percent = 2.64% to 3sf
The answer would be the last one- it separates dissolved substances.
Have a great rest of your day!
Ca=40
C=12
O=16
1 mole of CaCO3 has 100 grams
So 50 grams is 0.5 mole