Question

If an element has 12 protons and 17 neutrons, how many electrons must it have?

Answer 1

@kubofal

Answer 2

if given element is neutral, than it has to have same number of protons and electrons. so in this case it is 12 electrons.

Answer 3

thank you!

Answer 4

np

Answer 5

can you help me with this one? im trying to finish my final exam today because i have to go out of town because my grandpa is sick.

Why are the atomic masses of elements usually decimal numbers? Provide an answer using 3 – 4 sentences in your own words.

Answer 6

because we get atomic masses by multiplicating an atomic mass unit which is itself long decimal number. we multiplicate it with number of nucleons(protons, neutrons) which is whole number so we practically always get decimal numbers.

Answer 7

thank you, would you rather i do a new question thingy every time so i can give you medals or is this good?

Answer 8

its good

Answer 9

ok

In 3 – 4 sentences and in your own words describe how Mendeleev’s periodic table differs from Moseley’s.

Answer 10

different number of rows and columns but more importantly Moseley organised elements by their atomic numbers instead of atomic masses (which are not fundamental properties of elements). This gave birth to modern periodic table.

Answer 11

thank you,

What is the electron configuration of the element with 27 protons?

Answer 12

if given element is neutral than : \[1s ^{2}2s ^{2}2p ^{6}3s ^{2}3p ^{6}4s ^{2}3d ^{7}\]

Answer 13

How many electrons are in the highest energy orbital of the element copper?

Answer 14

1

Answer 15

Why is the first ionization energy of a nonmetal much higher than that of an alkali metal in its same period? Provide an answer using 3 – 4 sentences in your own words.

Answer 16

yeah

Answer 17

ionization energy is energy needed for separating electron from atom (so cation is forming). Nonmetals have much higher electronegativity (they hold electrons more strongly) due to more protons and shorter radius of atom in same period than alkali metals. So they need more energy to separate electron compared to alkali metals.

Answer 18

ok thank you so much for doing this

Why do compounds with strong intermolecular attractive forces have higher boiling points than compounds with weak intermolecular attractive forces? Provide an answer using 3 – 4 sentences and in your own words

Answer 19

because we need more energy to overcome strong intermolecular attractive forces. so simply their boiling points goes higher.

Answer 20

What is the reason the group 13 metals have a typical charge of 3+?

Answer 21

they donate 3 electrons