Question

IF UR ANSWER IS CORRECT I WILL MARK U BRAINLIEST... Q1. Give reasons for the following. i. Mass number is slightly less than the actual atomic mass. ii. Helium is chemically extremely unreactive. iii. The shells surrounding the nucleus of an atom are also called ‘energy levels’ . Q2. Answer the following 1)What is the relation between the number of protons and number of electrons in an atom? 2)What would be the reason for an element to have atoms with differing mass numbers.

Answer 1

Answer:

1. The mass number of an atom is slightly less than the actual atomic mass. ... The mass number is not equal to the atomic mass because of isotopes. Mass number is simply the number of protons and neutrons. The actual atomic mass of an atom is the weighted average of all existing atoms & isotopes per element
2. Helium is one of noble gases in group 8 of the Periodic Table. All these have a full outer electron shell. Elements are chemically reactive only if they have an unfilled out shell. ... It doesn't to gain or lose electrons to fill thus shell and is unreactive.
3. Energy levels (also called electron shells) are fixed distances from the nucleus of an atom where electrons may be found. Electrons are tiny, negatively charged particles in an atom that move around the positive nucleus at the center.

• What is the relation between the number of protons and number of electrons in an atom?

= The number of protons in the nucleus of the atom is equal to the atomic number (Z). The number of electrons in a neutral atom is equal to the number of protons. The mass number of the atom (M) is equal to the sum of the number of protons and neutrons in the nucleus.

• 2)What would be the reason for an element to have atoms with differing mass numbers.

=Different isotopes of the same element have the same atomic number. They have the same number of protons. The atomic number is decided by the number of protons. Isotopes have different mass numbers, though, because they have different numbers of neutrons.

Explanation:

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Answer 2

Answer:

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Explanation:

A major part of going green is taking into consideration the animals and plants that inhabit our planet. ... Going green starts by educating ourselves on how our choices can effect these plants and animals, and figuring out ways to save them and prevent the wildlife from harm.