Answer:
Explanation:
Num of molecules = num of moles * Avogadro's constant (6.02* 10^23)
But num of moles = reacting mass / molar mass
Molar mass of H20= 2*1 + 16 = 2+16 = 18g
Reacting mass of H20 = 0.55g
Therefore, num of moles of H20 = 0.55g/18g = 0.031 moles
Therefore, num of molecules of H20 = 0.031 * 6.02*10^23
= 1.87*10^22 molecules of H20
I’m pretty sure it’s A sorry if wrong
Among the choices, the unit of energy is calories. Answer in 1) is D. In 2) we are given with te mass , heat and temperature change. we just need to get the heat capacity and compare it with the following metals. The calculated heat capacity is 0.46 kJ/kg K. The answer is A. iron. In 3) we can compute the heat absorbed by the formula ΔH=mCpΔT. Cp of water is 4.18 J/g K. Answer of 3) is D. In 4) the formula used in Cp=ΔH/mΔT. Answer in 4) is A. The heat of enthalpy of fusion of ice is 80 cal/g. We convert this to J/g. Answer in 5) is B.334 J/g.
Compound made up of hydrogen and carbon
