Answer :
The atomic mass is the sum of the number of protons and neutrons in the nucleus of an atom.
Explanation :
Atomic number : it is defined as the number of protons or number of electrons.
Atomic number = number of protons = number of electrons
Mass number or atomic mass : It is defined as the sum of the number of protons and the number of neutrons.
Mass number or atomic mass = Number of protons + Number of neutrons
For example :
Number of protons in carbon = 6
Number of neutrons in carbon = 6
Mass number or atomic mass = Number of protons + Number of neutrons
Mass number or atomic mass = 6 + 6
Mass number or atomic mass = 12
Thus, the atomic mass is the sum of the number of protons and neutrons in the nucleus of an atom.
B. They work against a strong gravitational force
Answer:
Concentration of nitrate in the new solution = 0.007 M
Explanation:
Given:
Concentration nitrate solution = 0.070 m
Volume of aliquote of the nitrate solution is add = 10.0 ml
Total volume = 100 ml
Find:
Concentration of nitrate in the new solution
Computation:
Number of M. mole = 0.070 m x 10.0 ml
Number of M. mole = 0.7 m-moles
Concentration of nitrate in the new solution = 0.7 m-moles / 100 ml
Concentration of nitrate in the new solution = 0.007 M
Conduction.......................
Answer is: the oxidation number of oxygen must decrease.
Oxidizing agent is element (substance) that gain electrons in chemical reaction.
For example, balanced chemical reaction: C + O₂ → CO₂.
Oxygen change oxidation number from 0 to oxidation number -2 (reduction) and carbon change from 0 to +4 (oxidation)