Unit 5 objectives 1-8

Question 1

What is an atom?

Answer 1

Basic chemical element with protons, neutrons, and electrons

Question 2

Why do atoms of different elements have different characteristics?

Answer 2

Different number of electrons leads to different properties

Question 3

Atomic symbol
Number of protons
Number of electrons
Number of neutrons
Atomic number
Atomic mass/mass number
Number of energy levels with number of electrons in each

for carbon, nitrogen, sodium

Answer 3

C, 6, 6, 6, 6,12.001/12, 2 levels, 2 then 4 electrons

N, 7, 7, 7, 7, 14.007/14, 2 levels, 2 then 5 electrons

Na, 11, 11, 12, 11, 22.989/23, 3 levels, 2 then 8 then 1 electrons

Question 4

How is matter classified?

Answer 4

matter - pure substance - element/compound

matter - mixture - homo/hetero

Question 5

Neutral atom, ion, isotope

Answer 5

Neutral atoms are normal elements as you would find them on the periodic table, without any charge and neutrons so that when added to the number of protons you get the mass number. Ions are atoms that have a positive or negative charge to them because of electrons that were added (negative) or taken away (positive) from the original element. Isotopes are variations of the same element with more or less neutrons to change the mass of that specific variation.

Question 6

Ionic vs covalent bonds/what elements

Answer 6

Ionic - gives, metal to nonmetal
Covalent - shares, nonmetal and nonmetal

Question 7

K (1) and F (7) / Mg (2) and Cl (7) / Ca (2) and O (6) Lewis dot structures

Answer 7

check Learning Objectives

Question 8

Br + Br / Cl + H / O + H Lewis dot structures

Answer 8

check Learning Objectives

Question 9

What are group 18 metals called and why

Answer 9

Elements in group 18 of the periodic table all have 8 valence electrons. The octet rule is the tendency of atoms to prefer to have 8 atoms in the valence shell. Since atoms want 8 valence electrons and elements in group 18 already have that, they tend to not interact with other elements to get more electrons, they already have all they want.

Question 10

Anion vs Cation

Answer 10

Anion (negatively charged) Cation (positively charged)

Question 11

Polar vs Nonpolar sharing

Answer 11

Polar is unequally sharing towards electronegative ions, nonpoar sharing is when there is the same amount shared.

Question 12

Specific properties of water

Answer 12

Cappillary action:
Capillary action is the tendency of water to move through a narrow space without the assistance of or even opposite to the pull of gravity.

Surface tension:
Water molecules have a lot of surface tension. Take a water droplet for example. Where the droplet touches the ground surface and at the top of the semi circle of the droplet, there is only pulling to other bonds coming from one direction, so they are stronger and therefore stay together better.

heat capacity:
Water is able to absorb a large amount of heat before changing state or boiling, which is heat capacity.

density:
Uniquilly, the density of water in solid form is less than that in liquid form because in liquid form hydrogen bonds constantly break and reform, causing a higher density. However, in solid form the hydrogen bonds between molecules should separate the molecules, creating a lower density than in liquid form.

universal solevent:
Water is able to dissolve numerous substances and allow chemical reactions to take place, known as universal solvent.

Question 13

Proton, neutron, electron, neucleus

Answer 13

Proton - A particle in an atom with a positive electrical charge. The number of protons an element has also classifies what the element is and its atomic number.

Neutron - A particle in an atom that has no charge but has weight that when added to the proton weight gets you the mass number of a specific element.

Nucleus - The area in an element where the protons and neutrons are located.

Electron - Particles that are arranged in rings around the nucleus of an element that have a negative charge but virtually no effect on the mass of an element.

Question 14

Ion, isotope

Answer 14

Ion - An ion is an atom or molecule with an electric charge resulting from the loss or gain of more or more electrons. The net charge (total charge) of these atoms is not 0 due to the imbalance of positively charged protons and negatively charged electrons. If the atom has more protons than electrons, it will be a positive charge. If there are more electrons than protons, there will be a negative charge.

Isotope - Isotopes are versions (atoms) of the same element with different numbers of neutrons. Since the number of protons does not change but the neutrons vary, they will have different mass numbers (sum of protons and neutrons).

Question 15

Atomic number, mass number, atomic mass

Answer 15

Atomic Number - The number above the letter on an element on the periodic table that says how many protons that element has (and electrons if the element has no charge, which it does not on the periodic table.

Mass Number - The total number of protons and neutrons when added together in an element.

Atomic Mass - The average of the masses of isotopes of the same element.

Question 16

Ionic vs covalent bonding

Answer 16

Ionic Bonding - When a metal transfers one or more of its electrons to a non metal to obtain a full ring of valence electrons.

Covalent Bonding - A covalent bond is the back and forth movement of valence electrons between two atoms.

Question 17

Matter parts meaning

Answer 17

Compound - A compound is a pure substance in which two or more atoms of different elements are chemically bonded together. They can be covalent or ionic.

Pure Substance - The pure substance side has invariant chemical composition and distinct properties. These are elements which are fundamental substances that cannot be separated into simpler substances by chemical methods.
Another example are compounds which are compounds composed of two plus elements in fixed proportions that can be separated into simpler substances and elements only by chemical methods.

Mixture - Two or more pure substances that retain their individual identities and can be separated by physical methods.

Heterogenous Mixture - Have uniform composition and properties throughout in a mixture
Homogeneous Mixture - Are not uniform in composition and properties throughout in a mixture.

Question 18

Polarity, hydrogen bonding

Answer 18

Polarity - The slight difference in charge between atoms.

Hydrogen Bonding - When there is a slightly positive charge on the hydrogen side and a slightly negative charge on the oxygen side because oxygen is an electronegative atom and therefore attracts the electrons closer to it.

Question 19

Cohesion vs adhesion

Answer 19

Cohesion - When multiple of the same substance stick together.

Adhesion - When different substances stick to each other.

Question 20

Cappillary action and universal solvent

Answer 20

Capillary Action - When water moves through a narrow space without the assistant of the opposite pull of gravity.

Universal Solvent - The ability to dissolve numerous substances and allow chemical reactions to take place.

Question 21

Diagram 6 water properties

Answer 21

Check with Ria’s diagram

Question 22

The periodic number of an element refers to

Answer 22

Number of energy levels

Question 23

How do the six water properties relate to life today?

Answer 23

Check with Ria’s diagram

Question 24

Water molecules require a lot of energy to separate one from the others. What is this property of water and what is the factor causing it?

Answer 24

Specific heat, hydrogen bonding

Question 25

What property of water results in the accumulation of small amounts of water into larger amounts of water? The results in the rivers, lakes, streams, and even the oceans.

Answer 25

Cohesivness