Chemistry, 13.05.2021 01:00 hunterbrod9903

5. The heat of combustion of a sample of coal is 5500 cal/g. What quantity of this coal must be burned to heat 500.0 g of water from 20.0°C to 90.0°C?

6. The heat of combustion of a sample of coal is 5500 cal/g. What quantity of this coal must be
burned to heat 50.0 g of ice from 20.0°C to 90.0°C?

7. One gram of anthracite coal gives off 7000. cal when burned. How many joules is this?
How many grams of anthracite are required to raise the temperature of 4.0 L of water
from 20.0°C to 100.0°C?

8. A 500.0-g piece of iron is heated in a flame and dropped into 400.0 g of water at 10.0°C.
The temperature of the water rises to 90.0°C. How hot was the iron when it was first
removed from the flame? (Specific heat of iron is 0.473 J/gºC.)

HELP PLEASE
time left (1 hour and 20 mins)
22 points if you help!!

Answers: 3

Show answers

Another question on Chemistry

Chemistry, 22.06.2019 14:10

Precision can be defined as the o exact center of a data set. o reproducibility of a measured value. o correlation between two variables that are measured in a data set agreement between a measured value and an accepted value.

Answers: 2

Answer

Chemistry, 22.06.2019 17:10

Increasing the substrate concentration in an enzymatic reaction could overcome which of the following? a) the need for a coenzymeb) allosteric inhibitionc) competitive inhibitiond) insufficient cofactors

Answers: 1

Answer

Chemistry, 22.06.2019 18:30

Two people each hold the end of a rope and create waves by moving their arms up and down. this wave is best classified as a transverse wave because a) both the rope particles and the wave are moving in the same direction. b) the wave is moving up and down as the particles of the rope move horizontally. c) the wave is moving horizontally as the particles of the rope move up and down. eliminate d) the wave is moving in a parallel direction with the motion of the person's arms.

Answers: 3

Answer

Chemistry, 23.06.2019 00:00

Before it was launched, a helium-filled balloon had a pressure of 201 kpa at a temperature of 27°c. at an altitude of 15,000 m, the pressure had decreased to 2.5 kpa and the temperature had dropped to -14 °c. the volume of the balloon increased to 59.3 m3. what is the original volume of the balloon? 13 m3 0.85 m3 0.077 m3 1.17 m3

Answers: 3

Answer

You know the right answer?

5. The heat of combustion of a sample of coal is 5500 cal/g. What quantity of this coal must be bur...

Questions