structure of matter

Question 1

What is the basic unit of matter?

Answer 1

Atom

Question 2

True or False: Molecules are formed when two or more atoms bond together.

Answer 2

True

Question 3

Fill in the blank: The __________ is the central part of an atom that contains protons and neutrons.

Answer 3

nucleus

Question 4

What are the negatively charged particles in an atom called?

Answer 4

Electrons

Question 5

Which subatomic particle has a positive charge?

Answer 5

Proton

Question 6

What is the charge of a neutron?

Answer 6

Neutral

Question 7

Multiple Choice: Which of the following particles determines the atomic number of an element? A) Neutron B) Proton C) Electron

Answer 7

B) Proton

Question 8

What is an isotope?

Answer 8

Atoms of the same element with different numbers of neutrons.

Question 9

True or False: The mass number of an atom is the sum of protons and neutrons.

Answer 9

True

Question 10

What do you call the outermost electrons of an atom?

Answer 10

Valence electrons

Question 11

Fill in the blank: The __________ model describes the behavior of electrons in atoms as wave functions.

Answer 11

quantum

Question 12

Multiple Choice: Which of the following is NOT a state of matter? A) Solid B) Liquid C) Air Pressure

Answer 12

C) Air Pressure

Question 13

What is the primary force that holds atoms together in a molecule?

Answer 13

Chemical bond

Question 14

True or False: Ionic bonds involve the sharing of electrons.

Answer 14

False

Question 15

What type of bond is formed when electrons are shared between atoms?

Answer 15

Covalent bond

Question 16

Fill in the blank: A __________ bond occurs between a metal and a non-metal.

Answer 16

ionic

Question 17

What is the term used for the representation of a molecule using symbols and lines?

Answer 17

Structural formula

Question 18

Multiple Choice: Which of the following elements is a noble gas? A) Oxygen B) Helium C) Nitrogen

Answer 18

B) Helium

Question 19

What is the main difference between a compound and a mixture?

Answer 19

A compound has a fixed composition, while a mixture does not.

Question 20

True or False: All compounds are mixtures.

Answer 20

False

Question 21

What is the term for the smallest particle of a compound that retains its chemical properties?

Answer 21

Molecule

Question 22

Fill in the blank: The __________ theory explains how atoms combine to form molecules.

Answer 22

collision

Question 23

What is the name of the force that keeps protons and neutrons bound together in the nucleus?

Answer 23

Strong nuclear force

Question 24

Multiple Choice: Which particle has the least mass? A) Proton B) Neutron C) Electron

Answer 24

C) Electron

Question 25

What is the atomic mass unit (amu) used to measure?

Answer 25

The mass of atoms and subatomic particles.

Question 26

True or False: Electrons are found in fixed orbits around the nucleus.

Answer 26

False

Question 27

What does the term 'valency' refer to in chemistry?

Answer 27

The ability of an atom to bond with other atoms.

Question 28

what is the difference between a mixture and a pure substance?

Answer 28

pure substance only consists of one element or compound. mixtures consist of two or more different substances not chemically bonded together.

Question 29

classification of matter: pure substances and mixtures

Answer 29

pure substance - elements - compiunds mixtures - solutions, homogenous mixtures - solutions, heterogenous mixtures