M₁=6.584 g
m₂=4,194 g
m(H₂O)=m₁-m₂
w(H₂O)=m(H₂O)/m₁
w(H₂O)=(m₁-m₂)/m₁
w(H₂O)=(6.584-4.194)/6.584=0.3630 (36.30%)
the percentage by mass of water in the hydrate 36.30
It is called a spring tide
Answer:
C) ball rollinflown a hill
Explanation:
The question asks to identify the endothermic process in the list of options. By way of elimination, we have;
A) condensation of water on a wind shield of a car
Condensation is an exothermic process. That is, heat is given out as the gases change into the liquid state of matter.
B) formation of copper
This is an exothermic process. Capture of electrons by a cation is always exothermic.
C) ball rollinflown a hill
This is the correct option. Energy is absorbed by the ball as it moves on the hill
D) formation of ice from liquid water
Freezing is an example of exothermic reaction. Heat is given off to the surroundings.
E) oxide from copper and oxygen
Formation of metal oxides and most reactions involving oxygen are exothermic reactions,
Answer:
"Carbon dioxide (CO2) is one of a number of gases that are transparent to the visible light falling on the Earth from the Sun, but absorb the infra-red radiation (heat) emitted by the warm surface of the Earth, preventing its loss into space. During the geological history of the Earth the level of atmospheric CO2 has varied considerably and this has had an impact on the global temperature. A significant amount of this atmospheric carbon was sequestered or (removed from the atmosphere) and turned into inert material (coal, and oil) typically 300-360 Million years ago. All of the global ecosystems and species have adapted to a lower level of atmospheric CO2 and critically, human civilisation has also grown since that period. Since the industrial revolution humans have been burning sequestered CO2 in the form of coal, oil, and natural gas which has the result of releasing energy but also releases CO2 back into the atmosphere".
