#chemistry quiz questions

#Quiz

Oxygen has an atomic number of 8. Therefore, it must have

. 8 protons. 4 protons and 4 neutrons. 8 neutrons. A and C are correct. None of the above answers is correct

Nitrogen (N) has an electronegativity of 3.0 while the electronegativity of hydrogen (H) is 2.1. Which of the following statements is correct about ammonia (NH3)?

. Each hydrogen atom has a partial positive charge. The nitrogen atom has a strong positive charge. The nitrogen atom has a partial positive charge. Each hydrogen atom has a slight negative charge. There are covalent bonds between the hydrogen atoms

Each element is unique and different from other elements because of its

. Atomic weight. Atomic number. Mass number. Only A and C are correct. A, B and C are correct

The ionic bond of sodium chloride is formed when

. Chlorine gains an electron from sodium. Sodium and chlorine share an electron pair. Sodium and chlorine both lose electrons from their outer energy levels. Sodium gains an electron from chlorine. Chlorine gains a proton from sodium

A covalent chemical bond is one in which

. Electrons are removed from one atom and transferred to another atom so that the two atoms become oppositely charged. Protons or neutrons are shared by two atoms so as to satisfy the requirements of both. Outer shell electrons are shared by two atoms so as to satisfactorily fill the outer electron shells of both. Outer shell electrons of one atom are transferred to the inner electron shells of another atom. The inner shell electrons of one atom are transferred to the outer shell of another atom.

An atom has 6 electrons and 6 neutrons. It is electrically neutral. What is the mass number of this atom?

An atom becomes a cation if it

. Gains electrons. Loses electrons. Shares electrons. One or more of its electrons changes energy levels. Both A and C

Orbitals within shells around the nucleus of an atom can each hold no more than ________ electrons

How many electrons would aluminum, with an atomic number of 13, have in its valence shell?

. 13. 2. 8. 3. You cannot determine the number of electrons in the valence shell if all you know is the atomic number.

Which four of the 25 natural elements known to be essential to life make up approximately 96% of living matter?

. Carbon, sodium, chlorine, nitrogen. Carbon, sulfur, phosphorus, hydrogen. Oxygen, hydrogen, calcium, sodium. Carbon, oxygen, potassium, hydrogen. Oxygen, hydrogen, carbon, nitrogen