The specific heat capacity of a pure substance can be found by dividing the heat needed to change the temperature of a sample of the substance by the mass of the sample and by the change in temperature. the heat capacity of a certain substance has been measured to be2.76j·g°c suppose 466.g of the substance are heated until the temperature of the sample has changed by 39.4°c. write an equation that will let you calculate the heatqthat was needed for this temperature change. your equation should contain only symbols. be sure you define each symbol.

Q=m*c*ΔT=50674.7 Joules

Explanation:

By the definition described, the specific heat c is defined like this:

Where Q is the heat needed to change the temperature T of a mass m. So, multiplying both sides of the equation by m*ΔT we obtain

Then, we just substitute with the quantities and multiply them.

n2(g) + 3h2-> 2nh3(g)   this is the balanced equation

note the mole ratio between n2, h2 and nh3.   it is 1 : 3 : 2   this will be important.

moles n2 present = 28.0 g n2 x 1 mole n2/28 g = 1 mole n2 present

moles h2 present = 25.0 g h2 x 1 mole h2/2 g = 12.5 moles h2 present

based on mole ratio, n2 is limiting in this situation because there is more than enough h2 but not enough n2.

moles nh3 that can be produced = 1 mole n2 x 2 moles nh3/mole n2 = 2 moles nh3 can be produced

grams of nh3 that can be produced = 2 moles nh3 x 17 g/mole = 34 grams of nh3 can be produced

note:   the key to this problem is recognizing that n2 is limiting, and therefore limits how much nh3 can be produced.

c (diamond),

sio2 (quartz)