Chemistry Final Test

Question 1

What does WHMIS stand for?

Answer 1

Workplace Hazardous Materials Information Systems

Question 2

What is the purpose of WHMIS

Answer 2

To make sure employers and workers receive consistent and comprehensive health and safety information about hazardous products in the workplace.

Question 3

List the 6 (of 8) items on the whmis label

Answer 3

Product identifier, hazardous pictograms (hazard symbols), signal words, hazard statements, precautionary statements, supplier identifier, safe handling and precautions, reference to SDS.

Question 4

What does MSDS stand for?

Answer 4

Material safety Data Sheet. A document that contains information on the potential hazards (health, fire, reactivity and environmental) and how to work safely with the chemical product

Question 5

What is matter?

Answer 5

Matter is anything that takes up space and has weight

Question 6

Define physical change

Answer 6

Physical changes are changes that take place to the form of a substance, but don’t change the molecular structure of the sample.

EX: (cutting it in half, changing the shape, heating it up, freezing it, etc.)

Question 7

What are chemical changes?

Answer 7

Chemical changes are chemical reactions that change the molecular structure of the sample. Signs of a chemical change taking place: Changing colour, odours being produced, light, Temperature changing, gases being produced, precipitate (new solids are formed), Sample burning.

Question 8

What are the 3 subatomic particles?

Answer 8

Neutrons, Protons, and Electrons

Question 9

What are the charges of Neutrons, Protons, and Electrons

Answer 9

Neutrons have a neutral charge, Protons have a positive charge, and Electrons have a negative charge.

Question 10

List the four parts of atomic theory

Answer 10

Dalton’s atomic Theory:
-All matter is made of atoms. Atoms are indivisible and indestructible.
-All atoms of a given element are identical in mass and properties.
-Compounds are formed by a combination of two or more different kinds of atoms.
-A chemical reaction is a rearrangement of atoms.

Question 11

What did Lucretius and Democritus discover?

Answer 11

The word “atom comes from the Greek word “atomos” which means indivisible. Proposed that matter was composed of tiny indivisible particles.

(460-370 BCE)

Question 12

What did John Dalton discover?

Answer 12

Dalton said that like atoms will repel each other and unlike atoms will stay neutral in a mixture of gasses. He also stated that atoms of different elements have different sizes and mass. He basically created an atomic theory.

what he theorized:
-Elements consist of indivisible small particles (atoms)
-All atoms of the same element are identical, different elements have different types of atoms
-atoms can neither be created or destroyed

(1800s)

Question 13

What did joseph John Tomson discover?

Answer 13

Thomson stated that atoms are made of smaller things, subatomic particles. Thomson’s experiments with cathode ray tubes showed that all atoms contain tiny negatively charged subatomic particles (electrons). Thomson came up with the plum pudding model of the atom, which had negatively-charged electrons embedded within a positively-charged ‘soup’.

(1897)

Question 14

What did Hantaro Nagasaki discover?

Answer 14

Nagaoka rejected the plum pudding model and said that opposite charges are impenetrable. Leading to him proposing the Saturnian model like a plant where positive charged center is surrounded by negatively charged electrons that will eventually lose energy and spiral into the nucleus.

(1904)

Question 15

What did Ernest Rutherford discover

Answer 15

He discovered that an atom is mostly empty space and have a dense center. This was supported by his gold foil experiment where very few particles bounced back since they hit the dense and small nucleus. Rutherford established that the mass of the atom is concentrated in its nucleus. The light, negatively charged, electrons circulated around this nucleus.

(1911)

Question 16

What did Niel Bohr discover?

Answer 16

Bohr built off of Rutherford’s model and found that electrons can stay in stable orbits around the nucleus, though they can vary in energy levels/outer shells. According to the Bohr model, aka a planetary model, the electrons go around the nucleus of the atom in specific paths called orbits. When the electron is in one of these orbits, its energy is fixed.

(1913)

Question 17

What did Erwin Schrodinger discover?

Answer 17

He used mathematical equations to determine the likelihood of finding an electron in a certain position. He didn’t focus on electrons path but rather the locations. In 1926 formulated a wave equations that accurately calculated the energy levels of electrons in atoms.

Question 18

What did James Chadwick discover?

Answer 18

He found that the nucleus doesn’t only have protons, but also neutrons. As supported by his experiment. Chadwick measured the range of protons, and also measured how the new radiation impacted the atoms of various gasses. He found that the new radiation consisted of not gamma rays, but uncharged particles with about the same mass as the proton. These particles were neutrons.

Question 19

nuclear/isotope notation

Answer 19

element symbol (Ex: Li, Si, H), With atomic number (subscript) and Mass # (Super script)

Question 20

Hyphen notation

Answer 20

element name, hyphen (-), Mass #

Question 21

What is the history of the periodic table?

Answer 21

The earliest contribution was by Dmitrty Mendeleev in 1869 when he ordered the elements based on atomic weight and noted that similar chemical and physical properties appeared at regular intervals. At this time there were 63 elements known with many missing, so Mendeleev used estimates for properties and left gaps in the table. Between 1869 and 1913, new elements were discovered, and there were changes in the element names and symbols, the arrangement of the elements, and the addition of lanthanides and actinides. The atomic theory improved as many scientists learned more about the nature of atoms. In 1913 Henry Moseley developed a table in the order of increasing atomic number (instead of weight) which was more accurate and logical. With this method, he also found Mendeleev to have ordered the table by atomic number and was able to fix inconsistencies. Moseley’s table also allowed scientists to make predictions on unknown elements. Additional discoveries of subatomic particles also allowed us to have a deeper understanding of the elements.

Question 22

What is the difference between periods and groups?

Answer 22

Groups are the vertical rows, found in order of valence electrons while Periods are the horizontal rows, found in order of outer electron shells

Question 23

What are the properties of Alkali Metals?

Answer 23

Similarities:
-Metals
-1 valence electrons
-silvery-grey colour
-malleable and ductile
-conducts electricity
-soft metal
-Reactive with water
Differences:
-Different densities

Question 24

What are the properties of halogens?

Answer 24

Similarities:
-7 valence electrons
-non-metals
-very reactive
Differences:
-different colours
-different states

Question 25

What are the properties of noble gases?

Answer 25

Similarities:
-very stable (full valence electron shell)
-colourless gas
-glows when excited by electrons
Differences:
-Difference densities (Helium will rise while Argon will fall in air)

Question 26

Name two elements that are alkali metals

Answer 26

Ex: Lithium, Sodium, Potassium, Rubidium, Caesium, Francium

Question 27

Name two elements that are halogens

Answer 27

Ex: Fluorine, Chlorine, Bromine, Iodine, astatine, tennesscine

Question 28

Name two elements that are noble gases

Answer 28

Ex: Helium, Neon, argon, Krypton, Xenon, Radon, Oganesson

Question 29

What are Ions?

Answer 29

Ions are charged atoms, meaning they either have a positive charge (cation) or negative charge (anion)

Question 30

What is the difference between ionic compounds and diatonic compounds?

Answer 30

An ionic compound are pure substances consisting of one non-metal and one metal. While A molecular/covalent compound are pure substances consisting of two non-metal elements.

Question 31

What is a diatonic compound? What are the 7 naturally occurring diatonic compounds.

Answer 31

Diatonic compounds are elements that exist in nature as pairs (like twins). There are 7 naturally occurring diatonic compounds, they are H2, N2, F2, O2, I2, Cl2, Br2. Remember H O F Br I N Cl.