If a piece of lead has a volume of 19
mL, what is its mass?

The mass of lead is 216.6 g.

Explanation:

Given data:

Volume of lead = 19 mL

Mass of lead = ?

Solution:

To solve this problem we will apply the density formula.

In literature density of lead is 11.4 g/mL.

Density:

Density is equal to the mass of substance divided by its volume.

Units:

SI unit of density is Kg/m3.

Other units are given below,

g/cm3, g/mL , kg/L

Formula:

D=m/v

Now we will put the values.

11.4 g/mL = m/ 19 mL

m =  11.4 g/mL×19 mL

m = 216.6 g

The mass of lead is 216.6 g.

2fe + 3h2so4 -> fe2(so4)3 + 3h2

it is necessary to balance equations in order to get the proper amount of reactants as well as products in order not to make a miscalculation.

you cannot change the subscripts as that would change the substance itself. for instance, diatomic elements such as h2 only have the subscript two when a gas. another example would be so4, if you were to change the subscript, the element would no longer be sulfate.

we change the coefficients instead as that only changes the number of molecules rather than the substance itself.

hope this !