It depends. many of the websites i see answering the questions are all over the place, but good luck.
Answer:
To release 7563 kJ of heat, we need to burn 163.17 grams of propane
Explanation:
<u>Step 1</u>: Data given
C3H8 + 5O2 -----------> 3CO2 + 4H2O ΔH° = –2044 kJ
This means every mole C3H8
Every mole of C3H8 produces 2044 kJ of heat when it burns (ΔH° is negative because it's an exothermic reaction)
<u>Step 2: </u>Calculate the number of moles to produce 7563 kJ of heat
1 mol = 2044 kJ
x mol = 7563 kJ
x = 7563/2044 = 3.70 moles
To produce 7563 kJ of heat we have to burn 3.70 moles of C3H8
<u>Step 3: </u>Calculate mass of propane
Mass propane = moles * Molar mass
Mass propane = 3.70 moles * 44.1 g/mol
Mass propane = 163.17 grams
To release 7563 kJ of heat, we need to burn 163.17 grams of propane
Answer:
The number of neutron in the Aluminium Isotope is :
B. 14
Explanation:
Isotopes : These are the atoms which have same atomic number but have different mass number.
<u>This image shows the average atomic mass of Al element because it is in decimals</u>.
Atomic mass = 26.98154
(Note : mass number of single isotope can never be in decimals)
It is the average of mass of different isotopes of Al
Major Isotopes of 
are :
......atomic mass = 26
.......atomic mass = 27
mass of Al given in image(26.98) is nearly equal to mass of 2nd isotope(27)
mass of 
Now calculate the neutron in
Number of neutron = mass number - atomic number
= 27 - 13
Number of neutron = 14
(Atomic mass is same as mass number)
Answer: shining a bright light on the object and testing for decomposition
Decomposition is the separation of a molecule into its elements or simpler compounds.
And a chemical property is the ability of a
substance to combine or to become one or more substances.
Then, testing the ability of an object for decomposition is testing a chemical property.
