Answer:
C. The mass of an electron is much less than the mass of a proton or
a neutron.
Explanation:
When we compare the mass of an electron to that of proton or neutron, the mass of an electron is much less than the mass of a proton or a neutron.
Electrons are negatively charged particles in an atom
Protons are positively charged particles
Neutrons do not carry any charges.
- The relative mass of an electron compared to that of a proton is
- This is a very small value
- Electrons generally have mass of 9.11 x 10⁻³¹kg
- Protons weigh 1.67 x 10⁻²⁷kg
- Neutrons weigh 1.68 x 10⁻²⁷kg
We can see that electrons have very small mass and this is why when calculating the mass of an atom, we use the sum of the number of protons and neutrons.
Answer:
You are not using properly the function exponential in your calculator
Explanation:
When a number is too big or too small we use scientific notation. This is a number between 1 a 10 multiplied by a power of 10.
When you are writing 4.5*10^-9 you are actually writing 0.0000000045 in scientific notation.
When you enter this in the calculator you have to use the function EXP after the first two numbers.
Steps: 1) Enter 4.5
2) Enter EXP
3) Enter minus (-)
4) Enter 9
Answer:

Explanation:
Half reaction:
(1)
balance: 
(2)H and O balance in acidic medium:
(3) charge balance:
Hence balanced half-reaction: