1) Write the balanced chemical equation
2HCl + Na2 CO3 ----------> 2NaCl + H2CO3
2) Write the molar ratios:
2 mol HCl : 1 mol Na2CO3 : 2 mol NaCl : 1 mol H2CO3
3) Convert 0.15g of sodium carbonate to number of moles
3a) Calculate the molar mass of Na2CO3
Na: 2 * 23 g/mol = 46 g/mol
C: 12 g/mol =
O: 3 * 16 g/mol = 48 g/mol
molar mass = 46g/mol + 12g/mol + 48g/mol = 106 g/mol
3b.- Calculate the number of moles of Na2CO3
# moles = grams / molar mass = 0.15 g / 106 g/mol = 0.0014 mol Na2CO3
4) Calculate the number of moles of HCl from the molar proportion:
[0.0014 mol Na2CO3] * [2 mol HCl / 1 mol Na2CO3] = 0.0028 mol HCl
5) Calculate the volume of HCl from the definition of Molarity
Molarity, M = # moles / volume in liters
=> Volume in liters = # moles / M = 0.0028 mol / 0.1 M = 0.028 liters
0.028 liters * 1000 ml / liter = 28 ml.
Answer: 28 mililiters of 0.1 M HCl.
Answer:
2 Answers. The column is filled with the carrier (liquid or gas) before the sample is injected. Thus if there is no interaction between the sample and the column, then the fastest that the sample can get to the detector is the dead time denoted by tM in the diagram.
The average kinetic energy of 1 mole of a gas at -32 degrees Celsius is:
3.80 x 103 J
The relationship between volume and temperature of a gas, when pressure and moles of a gas are held constant, is: V*T = k.
FALSE
The relationship between moles and volume, when pressure and temperature of a gas are held constant, is: V/n = k. We could say then, that:
If the moles of gas are tripled, the volume must also triple.
If the temperature and volume of a gas are held constant, an increase in pressure would most likely be caused by an increase in the number of moles of gas.
TRUE
If the vapor pressure of a liquid is less than the atmospheric pressure, the liquid will not boil.
TRUE
35 - AB
36 - BD
33 - true
34 - False
20 - 6
21 - orthohombic
The chemical described above belongs to CLASS 1 EXPLOSIVES of DOT hazardous material classification. An hazardous substance is any substance which can cause adverse effects in humans when exposed to it. These substances are divided into different categories based on the way they react in different situations. It is mandatory that you aware of the kind of chemical you are working with when you are in the laboratory in order to take appropriate precautionary steps.
