Answer:
6.64 moles of carbon.
Explanation:
Given data:
Number of moles of C = ?
Number of moles of CCl₂F₂ = 6.64 mol
Solution:
In one mole of CCl₂F₂ there is one mole of carbon two moles of chlorine and two moles of fluorine are present.
In 6.6 moles of CCl₂F₂ :
Moles of carbon = 6.64 × 1 = 6.64 moles of carbon.
Moles of chlorine = 6.64× 2 = 13.28 moles of chlorine
Moles of fluorine = 6.64× 2 = 13.28 moles of fluorine
ions because it’s still the same element, however the charge has changed
Answer:- choice d is correct. Sr<Ca<Be .
Explanations:- Br, Ca, and Sr are all elements of same group as they all have 2 valence electrons. As we move down in a group, a new shell is being added that increases the size of the atom. As the size of an atom increases, it is easy to remove the electron from it's outer most shell in it's gaseous state. Since, Be is above Ca and Ca is above Sr. The size increases in the order, Be < Ca < Sr. It means Be is the smallest one of them and so it's hard to remove from it's outer most shell and hence it's ionization energy is higher.
Sr is largest one in these three elements and so it's easy to remove outer most electron from it that means the ionization energy is least. Ca is between Be and Sr.
So, an increasing order of ionization energy is Sr<Ca<Be . Choice D is correct.
Steel is an alloy and consists of more than one element (mainly iron and carbon), therefore steel is a mixture.