The answer is 4), see the picture
Answer:
hope you like it
Explanation:
because ouytermost shell contains two electrons
calcium is in group 2 so its valency is two valency is the number of outer shelll electrons it needs to have an stable outer shell . it needs 2 more .
Answer:
m = 998 g
Explanation:
Hello there!
In this case, according to the definition of the molar mass as the mass of one mole of the compound, it is possible to state the 1 mole of C8H18 has a mass of 114.26 grams; therefore, the mass in 8.65 moles turn out to be:

In agreement to the notation requirement.
Best regards!
A national day is a day on which celebrations mark the nationhood of a nation or state. It may be the date of independence, of becoming a republic, or a significant date for a patron saint or a ruler (such as a birthday, accession, or removal). The national day is often a public holiday.