Answer:
76
Explanation:
Alpha decay is one of the most basic forms of radioactive decay. It has an atomic mass of 4 and a proton number of two.
Undergoing an alpha decay will decrease the atomic mass by four and the atomic number by two.
In this particular question, we are particular about the atomic number. The atom has an atomic number of 78. So taking 2 off this gives 76
This equation C5H + O2 ---> CO2 + H2O has a mistake.
C5H is wrong. You missed the subscript of H.
I will do it for you assuming some subscript to show you the procedure, but you have to use the right equation to get the right balanced equation.
Assuming the tha combustion equation is C5H12 + O2 ---> CO2 + H2O
First you need to balance C, so you put a 5 before CO2 and get
C5H12 + O2 ---> 5CO2 + H2O
Now you count the hydrogens: 12 on the left and 2 on the right. So put a 6 before H2O and get:
C5H12 + O2 ---> 5CO2 + 6H2O
Now count the oxygens: 2 on the left and 16 on the right, so put an 8 on before O2:
=> C5H12 + 8O2 ---> 5CO2 + 6H2O.
You can verify that the equation is balanced
<span>8.278 g/mL
The definition of density is mass per volume. So what you need to do is divide the known mass by the known volume. So
1.663 g / 0.2009 mL = 8.27775 g/mL
But you also have to keep track of significant figures. Since both 1.663 and 0.2009 have 4 significant figures each, you need to round the result to 4 significant figures. So
8.27775 g/mL = 8.278 g/mL</span>
According to Boyle's Law, P1V1 = P2V2
where P1 and V1 are initial pressure and volume respectively. P2 and V2 are final pressure and volume receptively.
Given: P2 = 4 P1 and V1 = 10.0l
∴ V2 = 2.5 l
Answer: Final volume of system is 2.5 l
This is called the pedigree chart.
