Question

Number of protons, neutrons and electrons in the element
²³¹₈₉Y is
(a) 89, 231, 89 (b) 89, 89, 242
(c) 89, 142, 89 (d) 89, 71, 89

Answer 1

Answer:

answer is option c

Explanation:

electron = proton

mass no. = proton + neutron

neutron = 142

Answer 2

Dear Student,

◆ Answer -

(c) 89, 142, 89

● Explanation -

In element Yttrium, atomic no is 89. So no of protons and electrons are 89.

No of neutrons is given as difference between atomic mass and atomic number. So no of neutrons is 231-89 = 142.

Hence, answer is 89, 142, 89.

Thanks dear. Hope this is helpful to you..