Answer:
ffgghhhhhgffffffcvvvvvvvvvvvvvvvvvv
Explanation:
cccvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
The two ways that energy can be transferred are by doing work and by heat transfer.
If more reactant is added, the equation will shift to the right in order to make more product (which will increase the products)
Answer: 
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
Thus in the reactants, there are 2 atoms of hydrogen and 2 atoms of iodine .Thus there has to be 2 atoms of hydrogen and 2 atoms of iodine in the product as well. Thus a coefficient of 2 is placed in front of HI.
The balanced chemical reaction is:

Answer:
C.
The air pressure creates a vacuum in the straw that pulls the air into the liquid.