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BIO Ch. 2
chapter 2 final
Question | Answer |
---|---|
The 6 basic life elements | SCHNOPS sulfur, carbon, hydrogen, nitrogen, oxygen, phosporus |
All isotopes have the same number of ___ | protons |
What type of bond is formed when atoms share electrons? | Covalent |
Aquatic living things are able to survive the winter thanks to which property of water? | It is less dense as a solid than as a liquid |
The three isotopes of carbon 12C, 13C, and 14C have different numbers of ____? | neutrons |
The combined number of _____ will determine the number of electrons in orbital(s) around a neutral atom. | protons |
If an atom has an atomic number of 17 and a mass number of 35, the number of neutrons in its nucleus equals ___? | 18 (atomic number = protons) mass minus protons= neutrons. |
An electrically neutral atom with an atomic number of 7 will have ____ occupied electron shell(s). | 2 |
Which bond is most easily broken? | a hydrogen bond |
There are two ____ _____ bonds in water. | polar covalent |
hydrophobic molecules tend to be _____. | nonpolar |
The two parallel strands of DNA are held together by ____ bonds | hydrogen |
Hydrogen bonds form when ______. | a slightly negative atom is attracted to a slightly positive atom. |
The atom that has a nucleus with no neutrons is ____. | hydrogen |
How many naturally occurring elements are there? | 92 |
Atomic mass is the sum of ____ and _____. | protons and neutrons |
If the atomic mass is 15 and you have 8 protons, how many neutrons do you have? | 7 |
The atomic number of Na is 11, how many protons does Na have? | 11 |
If an element has 3 protons, how many electrons does it have? | 3 |
What is the Electric charge of an electron? | -1 |
What is the Electric charge of a proton? | +1 |
Proton, neutron, electron- Which ones contribute to the AMU? Which ones are located in the nucleus? Which one is located in the outer shell? What is that shell called? | protons & neutrons, protons & neutrons, electrons, electron shell |
What is it called when the atoms of the same element differ in the number of neutrons, but the number of protons and electrons stay the same? | isotopes |
What is the octet rule? | 2 electrons are allowed in the 1st shell and each one there after are allowed a max of 8 electron |
One the periodic table the horizontal rows are called? Vertical rows are called? | periods, groups |
What column of the periodic table are noble gases? Why are they stable-inert and rarely react with another atom? | VIII, the last shell has 8 electrons and do not bond with another element |
What type of bond do you call when an atom loses an electron to another atom? When an atom loses an electron, does it become + charged or – charged? | ionic bond, + |
What type of bond do have when electrons are shared? | covalent |
When 2 atoms are put together they make? Is an atom on it’s own make it an element? Molecule? | molecules, yes, no |
Covalent bonds, when atoms share an equal amount of electrons…example to hydrogens bonding-Is it polar or non-polar? | non-polar |
Covalent bonds- when atoms share an unequal amount of electrons…example H20-Is it polar or non-polar? | polar |
Referring to the outershell, an electron sharing and moving releases energy is called? | chemical reaction |
If something has a pH lower than 7, it is _______. If something has a pH higher than 7.1 it is ______. | acidic, base or alkyline |
What allows water molecules to hold onto each other without separating? | cohesion |
Water molecules has +/- charges, which allows them to _______ to polar surfaces, which is called? | adhere, adhesion |