Answer:
1. observations
2. hypothesis
3. experimentation
Explanation:
Observations are made, Hypothesies are formed from observations, and experimnets help alter and comfirm hypothesis.
Answer:
Explanation:
An oxidizing accepts an electron and becomes reduced while a reducing agent loses an electron and become oxidized.
Chemical equation:
1) 2 N₂H₄ + N₂O₄ → 3 N₂ + 4 H₂O
2) Hydrazine ( N₂H₄) is being oxidized
Dinitrogen tetroxide N₂O₄ is being reduced
3) The reducing agent is Hydrazine ( N₂H₄) and the oxidizing agent is dinitrogen tetroxide (N₂O₄)
The age of painting was determined from the decay kinetics of the radioactive Carbon -14 present in the painting sample.
Given that the half life of Carbon-14 is 5730 years.
Radioactive decay reactions follow first order rate kinetics.
Calculating the decay constant from half life:
λ
= 
= 
Setting up the radioactive rate equation:
Where 
k = decay constant =
ln 0.125 = 
-2.079=
t=
= 17185 years
t = 17185 years
Therefore age of the painting based in the radiocarbon -14 dating studies is 17185 years
Answer:
50 g of S are needed
Explanation:
To star this, we begin from the reaction:
S(s) + O₂ (g) → SO₂ (g)
If we burn 1 mol of sulfur with 1 mol of oxygen, we can produce 1 mol of sulfur dioxide. In conclussion, ratio is 1:1.
According to stoichiometry, we can determine the moles of sulfur dioxide produced.
100 g. 1mol / 64.06g = 1.56 moles
This 1.56 moles were orginated by the same amount of S, according to stoichiometry.
Let's convert the moles to mass
1.56 mol . 32.06g / mol = 50 g
Answer:
a) if the liquid is not vaporized completely, then the condensed vapor in the flask contains the air which is initially occupied before the liquid is heated. When calculating the molar mass of the vapor the moles of air which are initially present are not excluded, so that the molar mass of the vapor would be an increase in value.
b) While weighing the condensed vapor, the flask should be dried. If the weighing flask is not dried then the water which is layered on the surface of the flask is also added to the mass of the vapor. Therefore, the mass of the vapor that is calculated would be increase.
c) When condensing the vapor, the stopper should not be removed from the flask, because the vapor will escape from the flask and a small amount of vapor will condense in the flask. Therefore, the mass of the condensed vapor would be In small value.
d) If all the liquid is vaporized, when the flask is removed before the vapor had reached the temperature of boiling water, then the boiling
temperature of that liquid would be lower than that of the boiling temperature of the water.Therefore, the liquid may have more volatility.
