A. As pressure on the gas increases, the volume and temperature will both decrease
Answer:
(1)There are 1.5 moles of water in a 27 gram sample of water. The molar mass of water is 18.02 gmol g m o l .(2)
AnswersChemistryGCSEArticle
What is the mass (g) of 0.25mols of NaCl?
What you need for these equations are a calculator, periodic table and the following equation:
Mass (g) = Mr x Moles (important equation to remember)
In this case we already know the moles as it's in the question, 0.25 moles.
to find the Mr, you need to look at your periodic table. Find the relative atomic mass of Na and Cl and add the two numbers together.
Na = 22.99
Cl = 35.45
NaCl = 58.4
Now just put all of the numbers into the equation.
0.25 x 58.4 = 14.6g
All other elements react with other elements to form compounds. In the special case where the reaction produces fixed numbers of the same types of atoms in exactly the same configuration, we say the elements have formed a molecule.
Answer
find out the number of moles and use the molar ratio (numbers in front of formulas (in this case they are all 1) to determine how many moles of each product you are going to get theoretically
n=m/M is the equation to use to get moles here
30.8 gm/32.04 g/mol=0.9612 moles of the methanol and also of the formaldehyde so
0.9612 moles of the formaldehyde x molar mass (M) 30.73 g/mol= 29.54 gm which is the theoretical yield you already have the actual yield of 24.7 gm
then divide the actual by the theoretical to get the % yield which is 83.6%
Explanation: