Isotopes- ! it’d be much more appropriated if you added an explanation so i understand rather than just an answer!

13.

a.Atomic number of cadmium is 48

b.Number of protons = 48

c.Mass number = 115 u

d.Number of neutrons=67

e.Isotopic Symbol=

14. Elements which are isotopes are:

Explanation:

13.

a.Atomic number(Z):The number of protons present in the nucleus of the atom. Every element have fixed characteristic atomic number which decides its chemical property.It is represented by Z

for example : hydrogen atomic no. is 1 ,He is 2

So Cadmium has attained 48 atomic number.

b.Number of protons = Atomic number of the element

The atomic number of Cadmium is 48. Hence

Number of protons in Cadmium=48

c.Mass number(A) = Total number of protons and neutrons present in the nucleus of the atom.It is represented by A

Mass number = number of proton + number of neutron.....(1)

Cadmium has mass number of 115

d.Using equation (1),

Number of neutron = mass number - number of proton

Number of protons in Cadmium=48

Cadmium has mass number = 115

Number of neutron = 115 - 48

                                  =67

e.The format of symbolic representation of elements is given below

where X=symbol of element

Z= Atomic number

A= mass number

For Cadmium , X = Cd,Z = 48 , A =115

Symbol=

(Since this is isotope of cadmium hence it is isotopic symbol)

14.

Isotopes: These are the species which have same number of protons(or atomic number) but different number of neutrons(mass number).

So A ,C and E are isotopes

mass number: B=55 ,D=57

B and D are isotopes

in 1783 cavendish was working with his hydrogen gas and found that when he burned it and condensed the vapor it was water. this was very significant since it disproved the greek theory of elements completely since water was not a simple substance but the product of two gases. it was lavoisier who hearing of the experiment gave cavendish's gas the name hydrogen ("water-producer") and added that hydrogen burned by combining with oxygen and that water was a hydrogen-oxygen combination.

explanation: