False, the radiation from food and medical procedures have very little consequences. The radiation from a nuclear power plant can kill people which makes it a very large problem if not contained properly.
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First, we have to get:
1- The heat required to increase T of ice from -50 to 0 °C:
according to q formula:
q1 = m*C*ΔT
when m is the mass of ice = mol * molar mass
= 1 mol * 18 mol/g
= 18 g
and C is the specific heat capacity of ice = 2.09 J/g-K
and ΔT change in temperature = 0- (-50) = 50°C
by substitution:
∴q1 = 18 g * 2.09 J/g-K *50°C
= 1881 J = 1.881 KJ
2- the heat required to melt this mass of ice is :
q2 = n*ΔHfus
when n is the number of moles of ice = 1 mol
and ΔHfus = 6.01 KJ/mol
by substitution:
q2 = 1 mol * 6.01 KJ/mol
= 6.01 KJ
3- the heat required to increase the water temperature from 0°C to 60 °C is:
q3 = m*C*ΔT
when m is the mass of water = 18 g
C is the specific heat capacity of water = 4.18 J/g-K
ΔT is the change of Temperature of water = 60°C - 0°C = 60°C
by substitution:
∴q3 = 18 g * 4.18 J/g-K * 60°C
= 4514 J = 4.514 KJ
∴the total change of enthalpy = q1+q2+q3
= 1.881 KJ +6.01 KJ + 4.514 KJ
= 12.405 KJ
Measure the brightness of a star through two filters and compare the ratio of red to blue light.
Answers: -
For high kinetic energy, the object must have high speed of movement.
1) An airplane has a lot of kinetic energy. Airplanes move at high speed and thus posses a lot of kinetic energy.
2) A bullet from a gun has a lot of kinetic energy due to the high speed of bullet.
3) A formula one car moving at high speeds have a lot of kinetic energy.
4) A train moving at high speed has lots of kinetic energy.
5) An asteroid has a lot of kinetic energy due to it's high speed.
6) A roller coaster moving at high speeds have a lot of kinetic energy.
7) A missile fired from a fighter plane has lots of kinetic energy.
Carbon can react with oxygen to form carbon dioxide. Which of the following statements about this chemical change is true? ... Carbon and oxygen atoms are destroyed as new atoms are formed. Carbon and oxygen atoms have the same properties as molecules of carbon dioxide.
