Answer:
TRUE.
Explanation:
Mass Number is the sum of protons and neutrons present in the nucleus of an atom. Isotopy is a phenonmenon that occurs when atoms of same elements have different mass number (Number of neutrons).
2H isotope has 1 proton and 1 neutron.
3H isotope has 1 proton and 2 neutrons.
This meeans 2H isotope has fewer neutrons when compared to the 3H isotope. The correct option is TRUE.
Answer:
CaF2
Explanation:
Calcium fluoride is a solid formed by the chemical combination of Calcium (Ca) and Fluorine (F). Two molecules of fluorine (F2) and one molecule of Calcium (Ca) are needed to form the Calcium Fluoride molecule.
An ionic bond is formed between the Calcium and Fluorine atoms i.e. electrons are transferred from calcium atoms to fluorine atoms. The calcium ion is a cation with formula; Ca2+ while fluorine is an anion with formula; F-. Hence, it takes two molecules of Fluorine ion (F-) to form a relatively stable and neutral molecule with 1 molecule of Calcium ion (Ca2+).
Answer:
[H+] = 1.74 x 10⁻⁵
Explanation:
By definition pH = -log [H+]
Therefore, given the pH, all we have to do is solve algebraically for [H+] :
[H+] = antilog ( -pH ) = 10^-4.76 = 1.74 x 10⁻⁵
Answer:
a) 157.5 grams of aluminum.
b) 1 mol
c) 9 g
Explanation:
The reaction is :
As per balanced equation
a) 3 moles of hydrogen will be produced from two moles of aluminium.
The atomic mass of aluminium = 27
therefore
3X2 grams of hydrogen is produced from 2 X 27 grams of Al
1 gram of hydrogen will be produced from 
g
therefore 17.5 will be produced from = 9X 17.5 = 157.5 grams of aluminum.
b) as per balanced equation three moles or six gram of hydrogen is produced from 6 moles of NaOH.
Therefore 1 g of hydrogen will be produced from =
or 1 gram will be prepared from = 1 mole
c) from balanced equation three moles are produced from two moles of Al (27X2 = 54 g).
thus from 54 grams gives 6 grams of hydrogen
1 grams will give = 
