Calculus, originally called infinitesimal calculus or "the calculus of infinitesimals", is the mathematical study of continuous change, in the same way that geometry is the study of shape and algebra is the study of generalizations of arithmetic operations.
The number is written in scientific notation.
The significant figures are the numbers known precisely plus 1 digit that is uncertain.
When the numbers are expressed in scientific notation all the digits before 10^n are significant.
So, 7 and 8 are significant figures and the answer is that the number of significant figures is 2.
Answer: 2
Answer:- 21.4 grams of
are formed.
Solution:- The balanced equation is:

From this equation, lithium and nitrogen reacts in 6:1 mol ratio. Limiting reactant gives the theoretical yield of the product. We will calculate the grams of the product for the given grams of both the reactants and see which one of them gives the limited amount of the product. This limited amount of the product will be the theoretical yield.
The molar mass of Li is 6.94 gram per mol and for
It is 28.02 gram per mol. The molar mass of
is 34.83 gram per mol. The calculations for the grams of the product for given grams of both the reactants are shown below:

= 

= 
From above calculations, Li gives least amount of the product. So, 21.4 g of
are formed.
Explanation:
When the reaction takes place,2 grams of carbon dioxide will be made but vaporized into air.