The amount of energy that was used to heat Cu is 27.6 cal
<u><em>calculation</em></u>
Heat (Q) = M ( mass) x c(specific heat capacity) x ΔT( change in temperature)
where;
Q=?
M = 5.0 g
C=0.092 cal/g°C
ΔT = 80°c-20°c=60°C
Q is therefore = 5.0 g x 0.092 cal / g°c x 60°c =27.6 cal
Answer : 9773 kJ
Explanation:
Exothermic reactions are defined as the reactions in which energy of the product is lesser than the energy of the reactants. The total energy is released in the form of heat and 
for the reaction comes out to be negative.
To calculate the moles :
Given : Change in enthalpy on combustion of 1 mole of methanol = -1278 kJ
According to stoichiometry :
1 mole of methanol produce energy = 1278 kJ
Thus 7.647 moles of methanol produce energy =
Thus 9773 kJ of energy is produced from burning 245.0 g of methanol in excess oxygen
Chemical properties of matter can only be observed and measured by performing a chemical change.
- Density and boiling are not chemical changes.
- This leaves reactivity and combustion. Reactivity does not need to be observed at STP so the statement is wrong.
Combustion is the best answer.
Answer:
= 1.0593 g
Explanation:
1.1% NaCl by mass, means;
1.1 g per 100 g = 0.011
Therefore; the amount of NaCl present in 93.6 g of the solution is;
= 0.011 × 96.3 g
<u>= 1.0593 g</u>
