Answer:
Chemical reactions involve breaking chemical bonds between reactant molecules
Explanation:
In a chemical reaction, the atoms and molecules that interact with each other are called reactants. ... No new atoms are created, and no atoms are destroyed. In a chemical reaction, reactants contact each other, bonds between atoms in the reactants are broken, and atoms rearrange and form new bonds to make the products
Answer:

Explanation:
The atomic weight of oxygen = 15.9994 g
This mass corresponds to 1 mole of the oxygen atoms.
Thus,
15.9994 g mass of oxygen contains
atoms of oxygen.
1.4 kg = 1400 g ( 1 kg = 1000 g)
So,
1400 g mass of oxygen contains
atoms of oxygen.
Number of atoms in 1400 g of oxygen = 
Also, 1 atom of oxygen contains 8 protons
Charge of 1 proton = + 
So, Charge on 1 atom of oxygen = 
Thus,
Charge on
atoms of oxygen = 
Thus, positive charge in 1.4 kg of oxygen = 
Answer:
the scientific study of the relations between heat and other forms of energy
Answer:
cells=1
organ=3
organ system=4
tissue=2
Explanation:
i just did the question right now and i got them all correct.
I believe there are 3 significant figures B.