Answer:
30.25°C
Explanation:
The calorimeter is an equipment used to measure the combustion enthalpy of a substance. The heat loss in the reaction is used to heat the water and the equipment. By the conservation of energy:
Qcombustion + Qcalorimeter + Qwater = 0
Because there is no phase change:
Qcalorimeter = C*ΔT, where C is the heat capacity, and ΔT the variation in temperature (final - initial)
Qwater = m*c*ΔT, where m is the mass, and c is the specific heat (4.184 J/g°C).
The molar mass of lactose is 342.3 g/mol, so the number of moles in 2.50 g is:
n = mass/molar mass
n = 2.50/342.3
n = 0.0073 mol
Qcombustion = -5652 kJ/mol * 0.0073 mol
Qcombustion = -41.28 kJ
Qcombustion = - 41280 J
Thus,
-41280 + 1630*(T - 24.58) + 1350*4.184*(T - 24.58) = 0
(T - 24.58) * (1630 + 5648.4) = 41280
7278.4(T - 24.58) = 41280
T - 24.58 = 5.67
T = 30.25°C
Answer:
protons and neutrons are located in the nucleus.
The girl should first prevent getting scammed. She shouldn’t be sharing any personal information about herself or anybody else. Then to try to prove, she can maybe ask to face time during the day, or asks him out to go somewhere(park,movies,etc.,) but make sure you take someone with you like a trusted adult or someone older, and if he keeps making excuses and denying then it’s pretty clear it’s a catfish.
Answer:
the answer is organism tissue organ system organ cell
covalent bonds can form between two nonmetal atoms
covalent bonds can form between atoms of the same element
covalent bonds can form between atoms of different elements