Answer:
Explanation:
3. The number of electrons and neutrons in an atom are 13 and 14, respectively. Find out the mass number, atomic number, valency, and symbol of the element.
For a neutral atom. number of protons =number of electrons=13
so since atomic number is the number of protons =13
mass number = protons + neutons =14+13 = 27
atomic number 13 is Aluminum (AL-(see periodic table)
The electronic structure for 13 electrons is 1s2s2p63s23p1
so Al has 3 electrons which are VALIENT and can react and when it loses the 3 it will have CHARGE OF +3
Answer:
179.87 g/mol
Explanation:
First you need to determine the number of each elements in the molecule. This information comes from the molecular formula.
Ze(NO3)2 tells us that there is 1 Ze atom and 2 NO3 anions per molecule. each NO3 anion will have 1 nitrogen and 3 oxygens. Due to that, one molecule of Ze(NO3)2 will have 1 atom of Ze, 2 atoms of nitrogen (N), and 6 atoms of oxygen (O).
Next you need to add all of the individual atom's molar masses to get the over all molar masses. The molar masses of each element is in the question but it can also be found on the periodic table.
molar mass of Ze(NO3)2 = 55.85g/mol + (14.01g/mol*2) + (16.00g/mol*6)
molar mass of Ze(NO3)2 = 179.87 g/mol
I hope this helps.
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
PH + poH = 14
6.2 +poH = 14
poH = 7.8
It'll beginning to evaporate.