How many kilojoules are required to raise the temperature of a 150. g sample of silver from 25 °C to 135 °C? Silver has a specific heat of 0.235 J/g °C.

3.8775 kJ

Explanation:

The formula is Q=mcdeltat

We know m (mass) is 150, c (specific heat) is 0.235, and delta t (change in temperature) is 135-25=110

Plug that in and solve for Q

150*0.235*110=3877.5 J

The problem is that this is still in joules so we have to convert to kilojoules

3877.5 J * 1 kJ/1000 J = 3.8775 kJ

the answer to your question is c.

if you read the house of usher you should know that the house was haunted

"you start with 15.67 g mgco3-xh2o, when heated and all the water is removed, you are left with 7.58 g mgco3 only.

therefore, you had 15.67 - 7.58 = 8.09g h2o  

moles of each :

7.58g mgco3 = ? moles = 7.58g / 83.4g/mole = 0.09moles  

8 09g h2o = ? moles = 8.09g / 18g/mole = 0.44moles  

molar ratio between the two by dividing both numbers by the smallest number :

0.09 / 0.09 = 1  

0.44 / 0.09 = 4.8  

mgco3-5h2o"