Question

Ammonium acetate, NH4C2H3O2 is frequently used to create a buffer in solutions. Two moles of this compound contains:

A. 5 mole of oxygen.
B. 12 moles of hydrogen.
C. 14 moles of hydrogen.
D. 3 moles of carbon.

Which is true about Ba2+ and I- ?

A. They have the same number of neutrons
B. they have the same number of protons
C. they have the same number of electrons
D. they belong to the same group
E. none of the above

How many protons and electrons are present in one Br– ion?
A. 35 p, 35 e
B. 80 p, 34 e
C. 80 p, 81 e
D. 35 p, 36 e

The elements that touch the zig-zag line on the periodic table are known as
A. metals
B. nonmetals
C. metalloids
D. transition metals
E. none of the above

Answer 1

1. opton C, since one mole of ammonium acetae has 7 moles of hydrogens hence 2 moles of ammmonium acetate has 14 moles of hydrogens

2. option C, I^- has 54 electrons (53+1= 54) and Ba⁺² has has 54 elctrons (56-2=54)

3. option D,since atomic No of Br is 35 hence 35 protons (no of protons = Atomic No)

it has one -ve charge hence one more extra electron.

total 36 electrons are present in one mole of Br^-

4.option C, since Metalloids seperate the metal and non metals in periodic table