Missing question:<span> How many grams of oxygen are needed for complete combustion of the toluene?
Chemical reaction: </span>C₇H₈ + 9O₂ → 7CO₂ + 4H₂<span>O.
V(</span>C₇H₈) = 8,30 ml.
d(C₇H₈) = 0,867 g/ml.
n(C₇H₈) = V(C₇H₈) · d(C₇H₈).
m(C₇H₈) = 8,3 ml · 0,867 g/ml.
m(C₇H₈) = 7,19 g.
n(C₇H₈) = m(C₇H₈) ÷ M(C₇H₈).
n(C₇H₈) = 7,19 g ÷ 92,14 g/mol = 0,078 mol.
From chemical reaction: n(C₇H₈) : n(O₂) = 1 : 9.
n(O₂) = 9 · 0,078 mol = 0,702 mol.
m(O₂) = 0,702 mol · 32 g/mol = 22,5 g.
.50,mol
sodium acetate (NaCH3CO2) should be added to maximize the buffering
effect.
<span>
</span><span>A </span>buffering effect<span> is a process in which a psychosocial resource
reduces the impact of life stress on psychological well-being. Having such a
resource contributes to adjustment because persons are less affected by
negative life events.</span>
Answer:
the temperature changes finally to 339k because of the increase in pressure of the gas
A halogen is example of
nonmetal. The answer is letter A. When compounds containing halogens they are
called salts thus the name “salt – former”. Halogen consists of Fluorine,
Chlorine, Bromine, Iodine, Astatine.
Answer:
<h3><em>
Please make sure to re-write this on your own so your teacher doesn't think that your cheating!</em></h3>
Explanation:
A neutral atom will have the same number of electrons does protons. Since it has 4 protons, it must have an atomic number of 4. (That will make it beryllium.) Since it has 4 protons and 5 neutrons, it has a mass number of 9.
So the answer is 9
