Without its atmosphere, Earth would be
bombarded by meteorites, similar to mars, relatively lifeless. Without the atmosphere objects can just enter the atmosphere and cause serious harm to us, but with the atmosphere it basically reduces damage and shrinks it to size. Without the atmosphere earth would be like mars since it doesn't have a atmosphere. Without the atmosphere earth would be relatively lifeless since without air, us humans cant breathe so we will not survive.
Answer:

Explanation:
The given reactions are:
PbCl2(aq)⇌Pb2+(aq)+2Cl−(aq) 
AgCl(aq)⇌Ag+(aq)+Cl−(aq) 
Required reaction is:
PbCl2(aq)+2Ag+(aq)⇌2AgCl(aq)+Pb2+(aq)

Speed = distance/time
=> speed = 817/19 m/sec = 43 m/sec
hope it helps!
Answer:
There is a lot of empty space between them.
Explanation:
The kinetic molecular theory postulates that a substance is made up of tiny particles called molecules. The molecules of a gas are in constant random motion and collide elastically with each other. They also collide with the walls of the container.
The magnitude of intermolecular forces of attraction between gas molecules is very small. Hence gas molecules are largely apart with a lot of empty space between gas molecules.
Answer:
Water
Explanation:
Because the ratio with which hydrogen and oxygen combine is 2:1. I.e for every molecule of water there will always be
two atoms of hydrogen combined with one atom of oxygen.