C. C and Pb; Carbon and Lead being in the same group.
Answer:
True
Explanation:
Ex. People against vaccines tend to believe crazy theories over facts because they think they'll end up brainwashing them.
So half life is the time taken for a sample to decay to half its original mass, its a constant and applies to any original mass, it could be 5g or 1kg, it will take the same amount of time for the original mass to half. In this case the half life is 3 days.
After 3 days the sample will be at half its original mass, now 50g.
Now we can treat the 50g as if its a new sample. After another 3 days (6 days in total) there will be half of 50g left, = 25g.
Answer:
True.
Explanation:
To know which option is correct, let us calculate the number of mole present in 60g of calcium. This is illustrated below:
Mass of Ca = 60g
Molar Mass of Ca = 40g/mol
Number of mole Ca =....?
Number of mole = Mass/Molar Mass
Number of mole of Ca = 60/40
Number of mole Ca = 1.5 moles.
From the calculations made above, we can see that 1.5 moles are present in 60.0 grams of calcium
<em>Maybe</em>
<em>Mg+</em><em>Fe2O3</em><em>→</em><em>F</em><em>e</em><em>+</em><em>MgO</em>
<em>hope</em><em> it</em><em> helps</em>
