Answer:
36,000 miles in one hour.
Explanation:
Because there are 60 seconds in a minute and 60 minutes in an hour so to find out how many seconds are in an hour you multipy 60x60 to get 3600. Then to find out how many miles in the 3600 seconds you multiply 10 x 3600 to get 36000.
Answer: two or more different pure substances, which may be elements or compounds.
Explanation:
The term varieties of matter is kind of ambiguos since it is not defined.
The best approach to the question is to think of matter as it can be classified into to kinds: pure substaces and mixtures.
Elements and compounds are pure substances.
Elements are pure substances constituted by only one kind of atoms. An element cannot be divided into simpler substances either by physical or chemical media.
A compound is a chemical combination of two or more different elements. A compound can be divided into simpler substances by chemical reactions, but not by physical media. The properties of compounds are different of those of the elements of which they are constituted. The composition of a compoind (ratio among its elements) is fixed.
A mixture is the physical combination of two or more pure substances (either different elements or compounds) which can be mixed in any proportion. This is, its composition is variable. The substances that form the mixture can be separated by physical media.
The molar mass of CO2 is 44 grams per mole.
165 grams / 44 grams per mole of CO2 = 3.75 moles CO2
Using Avogadro’s law where 1 mole of substance equals
6.023 x 10^23 molecules
3.75 moles CO2 (6.023 x 10^23 molecules /mole) = 2.26 x 10^24 molecules CO2
Mass of methane takne = 1.5g
moles of methane used = masss / molar mass = 1.5 / 16 = 0.094 moles
mass of water = 1000 g
Initial temperature of water = 25 C
final temperature = 37 C
specific heat of water = 4.184 J /g C
1) Heat absorbed by water = q =m• C• ΔT = 1000 X 4.184 x (37-25) = 50208 Joules
2) Heat absorbed by calorimeter = Heat capacity X ΔT = 695 X (37-25) = 8340 J
3) Total heat of combustion = heat absorbed by water + calorimeter = 50208 + 8340 = 58548 Joules
This heat is released by 0.094 moles of methane
So heat released by one mole of methane =
- 622851.06 Joules = 622.85 kJ / mole
4) standard enthalpy of combustion = -882 kJ / mole
Error = (882-622.85) X 100 / 882 = 24.84 %
