Answer a is the correct one
He made a new approach when he discovered magnetism and electricity.
Answer:
As you move across a period the electrons are being added to the same shell. But, protons are being added as well. This makes the nucleus more positively charged and, increasing protons has a greater effect than electrons. So, there is a greater nuclear attraction and, because the electrons are being added to the same shell that shell gets pulled in more. This causes a decrease in atomic radius.
Explanation:
Answer:
= 25 g
Explanation:
Using the formula;
A = A₀ (1/2)^(t/h)
where A is the final amount,
A₀ is the initial amount of the substance,
t is the time and
h is the half-life of the substance,
In this case; the half life of U-238 h is equal to 4.47 billion years.
A = A₀ (1/2)^(t/h)
A = 50 (1/2)^(4.5 / 4.47)
= 24.88
<u> = 25 g</u>