Density = mass / volume
Density = 7.5 g / 5.0 cm3
Density = 1.5 g/cm3
Answer:
Conversion factor;
Molar mass;
Avogadro's constant and molar mass
Explanation:
- Firstly, an intermediate step is to define the conversion factor that will be then used in a conversion technique called dimensional analysis in order to convert from one unit to another. An example of a conversion factor would be, for example, 1 L = 1000 mL, which can be manipulated as a fraction, either
or
; - Secondly, in order to convert mass to moles, we need to know the molar mass of a compound which has a units of g/mol (that is, it shows how many grams we have per 1 mole of substance.
- Thirdly, Avogadro's constant,
tells us that there is
number of molecules or atoms in 1 mole of substance. We need two conversion factors to convert the number of molecules to a mass: firstly, we need to convert the number of molecules into the number of moles using Avogadro's constant and then we need to use the molar mass to convert the moles obtained into mass.
According to the chemical equation, the reaction ratio between O2 and CO2 is 2:1, which mean for every 2 moles of O2 reacted there is 1 mole of CO2 formed.
Use the molar mass and mass of O2 to find out the moles of O2: moles of O2 = mass of O2/molar mass of O2 = 8.94g/32.00g/mol = 0.2794 mole. Therefore, the moles of CO2 that formed is 0.2794moles/2 = 0.1397 mole
Use the moles and molar mass CO2 to find out the mass of CO2:
Mass of CO2 = moles of CO2 * molar mass of CO2 = 0.1397 mole * .44.01g/mole = 6.15 g.
So the answer is B 6.15g.