Safety glasses should be worn any time you are doing an experiment, especially one that involves chemicals or chemical reactions. They prevent chemicals or other materials from getting on or in your eye, and can prevent anything from mild discomfort to permanent blindness.
Some pairs of safety glasses have magnifying glasses on them, similar to bifocals. They can be used to more carefully examine something in an experiment.
"Indoor environments are much less polluted than outdoor <span>environments" is the best option since indoor environments often rely on separate air and ventilation systems. </span>
B. This is because the Hydrogen and Oxygen need balanced out.
Current-
C-1 | C-1
H-4 | H-2
O-2 | O-3
Adding a coefficient of 2 before oxygen in the reactants and H2O in the products would balance this equation
<span>CH4 + 2O2 → CO2 + 2H2O</span>
C-1 | C-1
H-4 | H-4
O-4 | O-4
The molecular weight of a given compound would simply the
sum of the molar weights of each component.
The molar masses of the elements are:
C = 12 amu
H = 1 amu
N = 14 amu
O = 16 amu
where 1 amu = 1 g / mol
Since there are 6 C, 5 H, 1 N and 2 O, therefore the
total molecular weight is:
molecular weight = 6 (12 amu) + 5 (1 amu) + 1 (14 amu) +
2 (16 amu)
molecular weight = 123 amu
Therefore the molecular weight of nitrobenzene is 123 amu
or which is exactly equivalent to 123 g / mol.
