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Flashcards in Important to remember for test Deck (23)
1

strong bonds between 2 atoms that share a pair of valence electrons

covalent bonds

2

strong attractions between ions (+ and - charged atoms)

ionic bonds

3

weak attractions between the partial charges of molecules with polar covalents

hydrogen bonds

4

is when the electrons are unequally shared by the atoms and are attracted more to one nucleus than the other

polar covalent bonds

5

because of the unequal distribution of electrons between atoms of different elements a slightly positive and a slightly negative charge develops

polar covalent bonds

6

an example of a polar covalent bond

water

7

combined with 2 hydrogen atoms and 1 oxygen atom

water H2O

8

the number of covalent bonds an atom can form

valence shell

9

usually equal to the number of electrons required to complete the outer most electron shell

valence shell

10

for this reason, the outermost electron shell of an atom is referred to as the valence shell

why the valence shell is important in forming covalent bonds

11

a difference in electronegatively between the two atoms that are covalently bound causes the bond to be more polar The atom that is more electronegative has the elections a larger amount of the time than the atom that is less electronegative

why is polar

12

the atom that has the electrons the majority of the time is partially negative charged, while the atom that has the electrons a smaller amount of the time is positively charged

a polar covalent bond

13

Adding up the # of protons and neutrons

how do you figure out the mass of an atom

14

atoms of the same element that have different number os neutrons

isotopes

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positive ions that are formed by losing an electron

cations

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negative ions that are formed by gaining an electron

anions

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are designated by their element name being altered to end in "ide"

anions

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movement of electrons from one element to another is referred to as

electron transfer

19

the lowest energy state

ground state

20

when the number of electrons is no longer equal to the number of protons each is now an

ion

21

formed between ions with opposite charges

ionic bonds

22

the attraction between cations and anions is called

ionic bonds

23

+ charged Na ions and - charged Cl ions bond together to make crystals of NaCl or table salt creating a crystalline with 0 net charge

an example of an ionic bond bond forming an ionic compound