naiinis naman sayo bhes pasko na oh gew

A chemical reaction that absorbs heat from the surroundings is said to be __________ and has a __________ DH at constant pressure.

• endothermic, positive

• endothermic, negative

• exothermic, negative

• exothermic, positive

• exothermic, neutral

The reaction is __________, and therefore heat is __________ by the reaction.

• exothermic, released

• exothermic, absorbed

• endothermic, released

• endothermic, absorbed

• thermoneutral, neither released nor absorbed

The value of DHe for the reaction below is -126 kJ. How much heat (in kJ) is released when 2.00 mol of NaOH is formed in the reaction?

• 252

• -126

• 7.8

• 63

• 3.9

The value of DHe for the reaction below is -790 kJ. The enthalpy change accompanying the reaction of 0.95 g of S is __________ kJ.

• -23

• 12

• -12

• 23

• -790

The value of DHe for the reaction below is -6535 kJ. How many kJ of heat are released in the combustion of 16.0 g of C6H6 (l)?

• 673

• 2.68 x 10³

• 5.23 x 10⁴

• -6535

• 1.34 x 10³

The value of DHe for the reaction below is -336 kJ. Calculate the heat (kJ) released to the surroundings when 23.0 g of HCl is formed.

• 211

• 177

• 70.7

• -336

• 2.57 x 10³

The specific heat capacity of lead is 0.13 J/g-K. How much heat (in J) is required to raise the temperature of 15 g of lead from 22eC to 37^oC?

• 29

• 5.8 x 10^-4

• -0.13

• 2.0

• 0.13

The specific heat of liquid bromine is 0.226 J/g-K. How much heat (J) is required to raise the temperature of 10.0 mL of bromine from 25.00eC to 27.30eC? The density of liquid bromine: 3.12 g/mL.

• 16.2

• 10.4

• 32.4

• 5.20

• 300

The specific heat capacity of methane gas is 2.20 J/g-K. How many joules of heat are needed to raise the temperature of 5.00 g of methane from 36.0eC to 75.0^oC?

• 22.9

• 88.6

• 429

• 0.0113

• 1221

The DH for the solution process when solid sodium hydroxide dissolves in water is -44.4 kJ/mol. When a 13.9-g sample of NaOH dissolves in 250.0 g of water in a coffee-cup calorimeter, the temperature increases from 23.0^oC to ________eC. Assume that the solution has the same specific heat as liquid water, i.e., 4.18 J/g-K.

• 14.0^oC

• 37.8^oC

• 40.2^oC

• 37.0^oC

• 35.2^oC