Explanation:
a) In 1 mole of methane there are 4 moles of hydrogen atom
Atomic mass of 1 mole of hydrogen atom = 1 g
Mass of hydrogen in 1 mole of methane = 4 × 1 g = 4 g
b) In 1 mole of chloroform there are 1 mole of hydrogen atom
Atomic mass of 1 mole of hydrogen atom = 1 g
Mass of hydrogen in 1 mole of methane = 1× 1 g = 1 g
c) In 1 mole of 
there are 10 moles of hydrogen atom
Atomic mass of 1 mole of hydrogen atom = 1 g
Mass of hydrogen in 1 mole of = 10 × 1 g = 10 g
d)In 1 mole of 
there are 12 moles of hydrogen atom.
Atomic mass of 1 mole of hydrogen atom = 1 g
Mass of hydrogen in 1 mole of = 12 × 1 g = 12 g
Mezoic era began 252m years ago and ended 6.6m years ago.
It was a time of geological and biological transition. During this era the continents began to drift to their present configuration.
3 of the largest mass extinction occurred at this era. One which include the dinosaurs.
I hope this helped. :)
Answer:
the answer should be A. the sum of all forces acting on an object
Explanation:
The kinetic energies of the particles (atoms, molecules, or ions) that make up a substance or object.
In a endothermic reaction energy from an outside source is continuously being added.
