Answer:
C. two atoms of oxygen.
Explanation:
Step 1: Data given
Silicon has 14 electrons
Silicon is part of Group IV, all the elements there have 4 valence electrons.
It can form a compound when 4 valence electrons bind with the 4 valence elctrons of silicon
A. four atoms of calcium.
Calcium has 2 valence elctrons. 4 atoms of calcium <u>cannot bind</u> on 1 atom of silicon since there are only 4 valence electrons.
B. one atom of chlorine.
1 atom of chlorine has 7 valence electrons. Chlorine can bind with an atom with 1 valence electron. Since silicon has 4 valence electrons, they will <u>not bind.</u>
Silicon can bind with 4 atoms of chlorine to form SiCl4
C. two atoms of oxygen.
Oxygen has 6 valence electrons, this means oxygen can bind with an element with 2 valence electrons.
Since silicon has 4 valence electrons, it <u>can bind</u> with 2 atoms of oxygen to form SiO2 (silicon dioxide).
D. three atoms of hydrogen.
Hydrogen has 1 valence electron. 1 hydrogen atom can bind with an element that has 7 valence electrons.
Three atoms of hydrogen can bind with an element that has 5 valence electrons.
Silicon <u>will not</u> bind with 3 atoms of hydrogen ( but can bind with 4 atoms of hydrogen)
The correct chemical formulae is CsBr
Answer:
4.8 g/mL is the density of chloroform vapor at 1.00 atm and 298 K.
Explanation:
By ideal gas equation:

Number of moles (n)
can be written as: 
where, m = given mass
M = molar mass

where,
which is known as density of the gas
The relation becomes:
.....(1)
We are given:
M = molar mass of chloroform= 119.5 g/mol
R = Gas constant = 
T = temperature of the gas = 
P = pressure of the gas = 1.00 atm
Putting values in equation 1, we get:

4.8 g/mL is the density of chloroform vapor at 1.00 atm and 298 K.