Explanation:
First, get both values into the same units
To covert from Kelvin to degrees C, subtract 273.15
1210 - 273.15 =936.85
Melting point of germanium=936.85 degrees C
Melting point of gold= 1064 degrees C
Therefore germanium would melt first because it has the lower melting point.
Answer: 3.5 moles V2O5
Explanation: First balance the chemical equation to find the stoichiometric factor between VOCl3 and V2O5
2 V2O5 + 6 Cl2 => 4 VOCl3 + 7 O2
So the mole to mole ratio is 2 moles V2O5 to 4 moles of VOCl3
Solution
7 moles VOCl3 x 2 moles V2O5 / 4 moles VOCl3 = 3.5 moles V2O5
Answer:
B. NO₂, nitrogen dioxide
Explanation:
Nitrogen dioxide is one of the oxides of nitrogen. It reacts highly and is very harmful for the health of humans. It is regarded as one of the pollutants of the air pollution. The chemical formula of Nitrogen dioxide is NO₂. This gas is produced during the manufacturing of the fertilizers in the industries. Burning of the fossil fuels also contribute in the emission of nitrogen dioxide. Two atoms of oxygen when reacts with one atom of Nitrogen, Nitrogen dioxide is formed.
Molarity = number of moles of solute / liters of solution
number of moles = molarity * liters of solution
number of moles of Na2C2O4 = 0.1 * 0.25 = 0.025 moles
Now, from the periodic table:
mass of Na = 22.9 grams
mass of C = 12 grams
mass of O = 16 grams
molar mass of Na2C2O4 = 2(22.9) + 2(12) + 4(16) = 133.8 grams
Therefore, one mole is equal to 133.8 grams. To know the mass of 0.025 moles, all you have to do is cross multiplication as follows:
mass = (0.025*133.8) / 1 = 3.345 grams