The specific heat of copper is 0.4 J/g^ *C If a sample of copper absorbs 480J of energy and its temperature changes from 20.0 ^* c to 60.0 ^ * C what mass of copper was heated?

The mass of copper that was heated is 30 g

Explanation:

The formula for the heat supplied, ΔH is;

ΔH = m·c·Δt

Where:

ΔH = Heat supplied = 480 J

m = Mass of the copper sample = Required

c = Specific heat capacity of copper = 0.4 J/(g·°C)

Δt = Change in temperature = T₂ - T₁ = 60° - 20° = 40°C

T₁ = Initial temperature = 20°C

T₂ = Final temperature = 60°C

Therefore, plugging the values, we have;

480 = m×0.4×40

m = 480/(0.4 × 40) = 30 g

The mass of copper that was heated = 30 g.

i just calculated it all out, and not including weekends, and all the different days off. as of this school year (2018-2019) students are spending 2198 hours in school this year

as given the equation is

2al + 6 hcl > 2 alcl3 + 3 h2(g)

as per equation two moles of aluminum reacts with six moles of hcl to give two moles of alcl3 and three moles of hydrogen gas

given: three moles of al are present and 7 moles of hcl

for three moles of aluminum nine moles of hcl will be required

however as 7 moles of hcl are present so the limiting reagent is hcl

hcl is going to decide the number of moles of product formed

when six moles of hcl are present = 3 moles of h2 are formed

when one mole of hcl is present == 3/6 mole sof h2 will be formed

when 7 moles of hcl are present = 3 x 7/ 6 moles of h2 will be formed = 3.5 moles of h2