There are 4 significant figures! Start counting after the first non-zero digit :)
Hope this helps.
Answer: 14.1g
Explanation:
Given that,
number of moles of SiO2 = 0.235 moles
Mass in grams = Z (let unknown value be Z)
Molar mass of SiO2 = ?
To get the molar mass of SiO2, use the atomic mass
Silicon = 28g;
Oxygen = 16g
i.e Molar mass of SiO2 = 28g + (16g x 2)
= 28g + 32g
= 60g/mol
Now, apply the formula
Number of moles = Mass / molar mass
0.235 moles = Z / 60g/mol
Z = 0.235 moles x 60g/mol
Z = 14.1 g
Thus, the mass of SiO2 is 14.1 grams.
Answer:
47911.1 pa
Explanation:
The SI base unit of pressure is pascal, which is N/m^2.
2200 kg is 2200*9.8=21560 N, and 4500 cm^2=4500/10000=0.45 m^2.
So the total pressure exerted on the ground (!!) is 21560/0.45= 47911.1 Pa.
Answer:
You should follow these steps:
Count each type of atom in reactants and products.
Place coefficients, as needed, in front of the symbols or formulas to increase the number of atoms or molecules of the substances.
Repeat steps 1 and 2 until the equation is balanced.
Explanation: