Simple,
take a look at your periodic table, if you have it labeled look at the Halogen
Group, it includes: Flourine, Chlorine, Bromine, Iodine, and Astatine.
Now, a period on the periodic table is read from left to right, and goes
down the rows of the periodic table.
Go to Period 5, go all the way to the Halogens, what is there?
Iodine.
Thus, your answer.
One of the causes of polarity is the unequal forces of the dipole forces due to differences in electronegativity. The more electronegative molecule tend to attract electrons, hence the polarity arrows point towards it. The electronegativity of Phosphorus and Fluorine is 2.19 and 3.98, respectively. Thus, it points outward towards the fluorine atoms.
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.