To calculate the mass of 9.30 moles of SiH4 in grams, we need to use the molar mass of SiH4. The molar mass of SiH4 can be calculated by adding the atomic masses of each atom in the compound.

The atomic mass of silicon (Si) is 28.0855 grams per mole.

The atomic mass of hydrogen (H) is 1.00794 grams per mole.

There is one silicon atom and four hydrogen atoms in each molecule of SiH4. Therefore, the molar mass of SiH4 is:

Molar mass of SiH4 = 1 * 28.0855 g/mol + 4 * 1.00794 g/mol = 32.1177 g/mol

Now that we know the molar mass of SiH4, we can calculate the mass of 9.30 moles of SiH4 in grams:

Mass = moles * molar mass

Mass = 9.30 moles * 32.1177 g/mol = 298.58 g

Therefore, the mass of 9.30 moles SiH4 in grams is 298.58 grams.