a. mol O₂=0.5
b. volume O₂ = 25 cm³
c. i. the total volume of the two reactants = 75 cm³
c. ii. the volume of nitrogen dioxide formed = 50 cm³
<h3>Further explanation</h3>
Reaction
2NO(gas) + O₂(gas) ⇒ 2NO₂ (gas)
a.
mol NO = 1
From the equation, mol ratio NO : O₂ = 2 : 1, so mol O₂ :

b.
From Avogadro's hypothesis, at the same temperature and pressure, the ratio of gas volume will be equal to the ratio of gas moles
Because mol ratio NO : O₂ = 2 : 1, so volume O₂ :

c.
i. total volume of reactants : 25 cm³+ 50 cm³=75 cm³
ii. the volume of nitrogen dioxide formed :
mol ratio NO : NO₂ = 2 : 2, so volume NO₂ = volume NO = 50 cm³
Answer:
Option C is the correct. Valence electrons have a higher energy level than those in other filled shells
Explanation:
Electrons must lose energy to move from the first to the second shell. FALSE
The electrons always win energy to move from the first to the second shell.
All the electrons in an atom have similar energy levels FALSE.
They are not neccesary similar. In hydrogen these are the level energy -13.6 eV
, -3.4 eV
, -1.51 eV
, -85 eV and -54 eV
Electrons do not have potential energy, just kinetic energy. FALSE
They have both.
Valencia electrons are the last electrons in the last layer. They have as much energy as possible and are responsible for forming bonds with other elements.
Answer : Option E) 50 grams.
Explanation : According to the solubility curves the compound
to dissolve at 50 °C in 100 mL of water will need 50 grams of the compound. It is clearly indicated in the graph which is marked with red that at 50°C approximately 50.4 grams of the compound
will be needed to dissolved in 100 mL of water to form a solution.
Answer:
25 g/hr
Explanation:
Remember that the rate of reaction refers to the rate at which reactants are used up or or the rate at which products appear.
Hence;
Rate of reaction = mass of reactant used up/time taken
Mass of reactant used up= 2g
Time taken = 5 minutes or 0.08 hours
Rate of reaction = 2g/0.08 hours = 25 g/hr