2 NaOH (s) + CO₂ (g) → Na₂CO₃ (s) + H₂O (l)
Explanation:
The most probably chemical reaction is:
2 NaOH (s) + CO₂ (g) → Na₂CO₃ (s) + H₂O (l)
Sodium Hydroxide (solid) + Carbon Dioxide (gas) → Sodium Carbonate (solid) + Water (gas)
In this reaction the water you obtain have to be in liquid form because the reaction takes place at room temperature. However because the student left the beaker for 24 hours, the water have a plenty of time to evaporate, so in the end only sodium carbonate (Na₂CO₃) remained in the beaker.
number of moles = mass / molar weight
number of moles of NaOH = 0.4 / 40 = 0.01 moles
Taking in account the chemical reaction, we devise the following reasoning:
if 2 moles of NaOH produce 1 mole of Na₂CO₃
then 0.01 moles of NaOH produce X mole of Na₂CO₃
X = (0.01 × 1) / 2 = 0.005 moles of Na₂CO₃
mass = number of moles × molar weight
mass of Na₂CO₃ = 0.005 × 106 = 0.53 g
mass of Na₂CO₃ = mass of beaker and its contents after 24h - mass of empty beaker
mass of Na₂CO₃ = 113.09 - 112.58 = 0.51 g which is close the theoretical value of 0.53 g.
Learn more about:
number of moles
#learnwithBrainly
According to the stoichiometry of the reaction of mercury(II) oxide 1.477 g of oxygen would be produced by heating 20 g of mercury (II) oxide if 18.6 g of mercury is produced.
Stoichiometry is the determination of proportions of elements or compounds in a chemical reaction. The related relations are based on law of conservation of mass and law of combining weights and volumes.
Stoichiometry is used in quantitative analysis for measuring concentrations of substances present in the sample.
433.18 g mercury (II) oxide gives 32 g oxygen thus, 20 g of mercury (II) oxide will produce 20×32/433.18= 1.477 g of oxygen.
Thus, 1.477 g of oxygen would be produced by heating 20 g of mercury (II) oxide if 18.6 g of mercury is produced.
Learn more about stoichiometry,here:
#SPJ6
(2) 42 g (4) 104 g
Answer: It's 104 g
Explanation: yes
b) a period of time when temperatures across the planet are colder than normal
c) a characteristic of summer that returns seasonally
d) the gain of heat in coastal areas from El Niño storms
Global Warming is a gradual increase in the overall temperature of the earth's atmosphere.
So, i believe the answer to your question would be a) a recent increase in the average global temperatures near Earth's surface
a
seoosososossosososososososs
Answer:
3,495.02
Explanation: TRY THAT FOR AN ANSWER