Calculate the number of moles in 35.7 g of CH4

Explanation:

First, find the molar mass of CH₄

This compound is made of carbon (C) and hydrogen (H). Look on the Peirodic Table for the masses of both elements.

Now, count the number of moles in the compound. There is no subscript on C, indicating 1 mole. There is a subscript of 4 on H, indicating 4 moles. We must multiply the molar mass of hydrogen by 4.

Add the 2 masses.

Next, find the number of moles in 35.7 grams.

Use the molar mass of CH₄ as a ratio.

Since we want the units of grams CH₄ to cancel when we multiply, we must flip the ratio.

Multiply by 35.7 grams.

The grams of CH₄ will cancel each other out.  Since there is a 1 in the numerator, we can also move 35.7 to the numerator.

The original measurement given, 35.7 grams, has 3 significant figures (3, 5, and 7), so we must round to 3 sig figs.

For this number, it is the hundredth place.

The 5 in the thousandth place tells us to round the 2 to a 3.

There are about 2.23 moles of CH₄ in 35.7 grams.

the objects have the same charge is correct.

nathan lee