WorksheetsEnergetics and Moles
Total questions: 19
Worksheet time: 18mins
Some white anhydrous copper(II) sulfate powder is put into a beaker of water and stirred. What would show that the process was exothermic?
A blue solution is formed
The beaker feels cooler
The beaker feels warmer
Exothermic reactions are ones that.....
Release energy to the surroundings
Absorb energy from the surroundings
Remain at a constant temperature
Decrease in temperature
Adding energy to get a reaction started is.....
Activation energy
Catalytic
never needed
needed for breaking bonds
endothermic reactions ........
have more energy in their products
have less energy in their products
have more energy in their reactants
have the same amount of energy in reactants and products
Two examples of an exothermic reaction are......
Metals and acids
Photosynthesis
Thermal decomposition
Combustion
What can you calculate using this equation? Q=mcΔT
The energy absorbed or lost by a substance
The energy given out or taken in by a reaction
The energy given out by a reaction for 1 mole of a substance
Specific heat capacity of water is always......
4 kJ/g
4J/g
4.18kJ/g
4.18J/g
Specific heat capacity of solutions is the same as for water because......
Solutions have the same mass as water
Solutions have the same energy as water
Solutions are aqueous
Solutions contain water and other liquids
What is the difference between Q and ΔH ?
Q is for any amount of a substance, ΔH is for 1 mole
Q is for 1 mole of a substance, ΔH is for any amount
They are both the same
The have the same number but if one is positive, then the other must be negative
What is the connection between the energy absorbed or lost by the water and the energy change for the reaction?
They are always positive
They are always negative
They are both the same
The have the same number but if one is positive, then the other must be negative
the following diagram shows the energy profile for the reaction between sodium hydrogen carbonate (NaHCO3) and Hydrochloric acid.
find the correct relationship between the type of the reaction and statement about energy of reactants and products.
endothermic - products have more energy than the reactants
exothermic - products have less energy than the reactants
exothermic-products have more energy than the reactants
endothermic - products have less energy than the reactants
How do we calculate the molar mass (aka the mass of one mole) of a substance
Add up the atomic numbers of all the atoms in the formula
Add up the atomic masses of all the atoms in the formula
Guess
Look it up on Google
58.5g/mol
The mass of one mole of an element is equal to
its atomic number from the periodic table.
its atomic mass from the periodic table.
its atomic mass from the periodic table, but in grams.
its atomic number from the periodic table, but in grams.
Mass divided by RAM/RFM is how to calculate.......
Number of moles of a substance
Concentration of a substance
Enthalpy change of a substance
Shivani measures out 6.0 moles of epsom salt (MgSO4) to put in her bath. How many grams of MgSO4 went in the bath?
3.6 x 1024 g
720 g
0.050 g
340 g
Determine the mass of 4.20 moles of C6H12
353 g
0.0499 g
337 g
2.53 x 1024 g
How many grams are in 1.2 moles of neon?
0.059 grams
7.2 x 1023 grams
2.0 x 10-24 grams
24 grams
