When balancing a chemical equation, what are the large numbers that we adjust?

Coefficients

Explanation:

Chemical equations are first written as a skeleton equation, which includes how many atoms each element and compound has. Skeleton equations are not 'balanced' because the number of atoms of each element on the left side (reactants) is not equal to the right side (products).

To balance a chemical equation, you can write coefficients in front of single elements and compounds. The coefficient multiplies with each single element and with each element in the compound.

For example, in this skeleton equation:

H₂ + Cl₂     =>       HCl

Reactants:          Products:

2 hydrogen         1 hydrogen

2 chlorine            1 chlorine

Write the coefficient 2 in the products.

H₂ + Cl₂     =>       2HCl

Now both reactant and product sides have 2 chlorine and 2 hydrogen, so the equation is balanced.

first one is the correct answer

number of molecules / avogadro's number * molecule molecular = mass

explanation:

we define a gram-molecular weight as the mass of one mole of any element or compound. a mole contains avogadro's number of units (molecules) –  

6.022

x

10

23

. so, dividing the number of molecules by avogadro's number gives us the number of moles. multiplying that by the molecular weight gives us the mass. from the periodic table we find the gram-molecular weight of u to be238 and of f to be19. so,  

u

f

6

will have a gram-molecular weight of 352g.