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WorksheetsCh2- Chemistry of Life
Total questions: 41
Worksheet time: 1hrs 22mins
What are the top 5 most common elements in the human body?
Hydrogen, Oxygen, Carbon, Nitrogen, and Phosphorus
Aluminum, Copper, Gold, Arsenic, and Sodium
Lead, Vanadium, Titanium, Tin, and Mercury
Chromium, Silver, Niobium, Ruthenium, and Rhodium
Atoms
Tiny micro-organisms
The substance that makes up Tin
The building blocks for ALL substances (Electrons, protons, and neutrons)
The substances that make up only Noble Gases
Elements
Substances that consist of multiple kinds of atoms
Substances that consist of only one kind of atom
Only Noble Gases are elements
Mixed substances
Radioisotopes
Isotopes that travel through radio waves
Isotopes that travel through soundwaves
non-radioactive isotope
Some atoms are unstable and emit subatomic particles/energy when their nucleus breaks down (radioactive isotope)
Atomic number
Equal to the number of protons and determines the element
Number of atoms in an element
The number of atoms in something
The number of atoms
Mass Number
The average mass of Noble Gases
Determines the elements
Protons and neutrons in nucleus
The average mass of all the elements
Protons have what kind of charge?
140 watts
Negative
Nuetral
Positive
What kind of charge do neutrons have?
Positive
Negative
Neutral
140 watts
What charge do electrons have?
Positive
Negative
Nuetral
140 watts
What happens if you change the number of protons of an atom?
A new element forms
The element stays the same
Nothing happens
Nothing happens
What happens if you change the number of neutrons of an atom?
Nothing happens
The element changes
Nothing happens
Effects isotopes (different forms of the same element)
What happens if you change the number of electrons of an atom?
Nothing happens
Effects ions (atoms positive or negative charge)
Nothing happens
The element changes
What is radioactive decay?
The rate in which soundwaves decay as they travel
Decay of non-radioactive atoms
Radioisotopes emit subatomic particles of energy when their nucleus breaks down, transforming one element into another at a constant rate
The growth of healthy cells
What are 5 key things to know about electrons?
Electrons are in outer shells around the nucleus and fill shells from the inside out
Innermost shell can contain up to 2 electrons
The outermost sublevel (valence shell) can contain up to 8 electrons
Atoms with vacancies in their outer shell tend to give up, acquire, or share electrons (All elements except for noble gases)
All of the above
Which elements on the periodic table naturally have a full outer shell of electrons?
Noble gases
Metals
Non-metals
Alkaline-earth metals
Since noble gases naturally have a full outer shell, what does this mean about all of the other elements on the periodic table?
They all have full outer shells
They only lose electrons
The other elements share and trade electrons
They don't share or trade electrons
Electronegativity
Measure of electricity
A measure of an atom's ability to pull electrons from another atom
Measure of isotopes
Measure of negativity
Chemical bond
An action that occurs when atoms repel each other
When two elements remain separate
When atoms repel each other
An attractive force existing between 2 atoms when their electrons interact
Molecule
1 atom
2 or more atoms joined in chemical bonds
1/2 of an atom
1/100 of an atom
What is an ionic bond?
A strong mutual attraction between 2 oppositely charged ions
Large difference in electronegativity
Ex: Na+ Cl- (Table salt)
All of the above
Covalent Bond
Two atoms with similar electronegativity unpaired electrons sharing a pair of electrons
Can be stronger than ionic bonds and covalent bonds can be nonpolar or polar
Atoms can share one, two, or three pairs of electrons (single, double, or triple covalent bonds)
All of the above
Nonpolar covalent bond
Atoms sharing electrons equally
formed between atoms with identical electronegativity
Ex: H-H (H2)
All of the above
Polar covalent bonds
Atoms share electrons unequally, one atom has a more (partial) negative charge, the other is more (partial) positive
They have different electronegativity
Ex: H2O
All of the above
Hydrogen bonding
A weak attraction between a highly electronegative atom (has a partial negative charge) and a hydrogen atom (has a partial positive charge) taking part in a separate polar covalent bond
Bonding that doesn't occur with hydrogen atoms
Bonding between only noble gases
Bond that deals with atoms that have no electronegativity
What is different about hydrogen bonds as compared to ionic and covalent bonds?
They form molecules
Hydrogen bonds don't include hydrogen atoms
Unlike ionic and covalent bonds, hydrogen bonds do NOT form molecules
Hydrogen bonds only deals with noble gases
Generally, why is water so important to living organisms?
Living organisms are mostly water; all the chemical reactions of life are carried out in water
You can drink it
It's healthier than Coke
It's good for cleaning stuff
How would you describe the structure of a water molecule?
Wet
Overall, water (H2O) has no charge, the water molecule is polar, oxygen atom is still slightly negative, and hydrogen atoms are slightly positive
Watery
Liquid like
What are the unique properties of water due to?
Oxygen atoms
Chlorine
The hydrogen bonds that form between water molecules
Fluoride
What are 3 unique properties of water?
Solvent (universal solvent)
Water's cohesion
Density
All of the above
Why is water called the universal solvent?
Because it can dissolve so many elements
The collective strength of many hydrogen bonds pull most bonds apart and keeps them dissolved
Ex: water dissolves polar molecules like salts
All of the above
What causes water's unique cohesion?
Hydrogen bonds give water cohesion, which is when molecules resist separation from one another
Ex: Surface Tension
Ex: capillary action (Plants draw water up from roots)
All of the above
What causes water's unique density?
Hydrogen bonds form a lattice during freezing that has more space between the molecules than the same molecules when water is liquid
Ice is less dense than liquid water
Bodies of water freeze from the top down
All of the above
Hydrophilic (water-loving)
Polar molecules that aren't dissolved by water
It hates water
Polar molecules that are dissolved by water
Won't dissolve in water
Hydrophobic (water-fearing)
Nonpolar molecules are NOT dissolved by water (Ex: oil)
Polar molecules
Can be dissolved by water
Loves water
What is pH a measure of?
Measure of protons
Measure of nuetrons
pH is a measure of the number of hydrogen ions in a solution
Measure of electrons
What does 7 on the pH scale mean?
pH 7= neutral (pure water)
Extremely acidic
Extremely basic
It means absolutely nothing
What does 0 on the pH scale mean?
0 pH= strong base
0 pH= strong acid
0 pH= neutral
Base
What does 14 on the pH scale mean?
14 pH= strong acid
14 pH= neutral
14 pH= nothing
14 pH= strong base or alkaline
Compare acids vs. bases
They're the same thing
Acids donate hydrogen ions; pH below 7
Bases accept hydrogen ions; pH above 7
One is acid the other is a base
They are both neutral on the pH scale
What is salt?
NaCl
The stuff in oceans
A compound that dissolves easily in in water and releases ions other than H+ and OH-
The stuff we put on fries
What is a buffer system?
A set of chemicals (a weak acid or base and its salt) that can keep the pH of a solution stable
Chemicals that make the pH of a solution unstable
Random chemicals
A system
