Basic Chemistry, Properties of Water, Acids, Bases, and pH

How many electrons are in each orbital?

1st= 2, 2nd = 8, 3rd = 8

What is H2O made of?

2 hydrogen and 1 oxygen

How many electrons would be present in the outer orbital if the atomic number is 16?

6

What is a neutral pH and an example?

7 (water)

ionic bond

A chemical bond resulting from the attraction between oppositely charged ions. One atom lost an electron the other gained an electron

covalent bond

A chemical bond that involves sharing a pair of electrons between atoms in a molecule

surface tension

A measure of how difficult it is to stretch or break the surface of a liquid

high specific heat

A property of water. Water can absorb lots of heat before changing temperature

Element

A pure substance made of only one kind of atom

Adhesion

An attraction between molecules of different substances (water hydrogen bonding with other polar or ionic molecules)

Cohesion

An attraction between molecules of the same substance (water hydrogen bonding with water)

Isotope

Atoms of the same element that have different numbers of neutrons

hydrogen bond

Attraction between a slightly positive hydrogen atom and a slightly negative atom.

Atom

Basic unit of matter

Main elements in living things

CHNOPS (carbon, hydrogen, nitrogen, oxygen, phosphorus, sulfur)

Which molecule has a polar covalent bond?

H2O

When moving away from pH 7, are substances becoming weaker or stronger acids and bases?

Stronger

What are valence electrons?

The electrons in the outermost shell of an atom

net charge

The sum of negative and positive charges.

Why is water more negative near the oxygen atom?

There is an uneven distribution of electrons. Electrons spend more time near the oxygen atom.

What is the benefit of high specific heat capacity?

Water is slow to heat up slow to cool down, moderates temperature changes in in nature

capillary action in plants

a cohesive and adhesive force due to attraction between water and small tubes in the plant.

Acid and Bases

acid = many hydrogen ions, base = many hydroxide ions

ion

atom that has a positive or negative charge

What kind of bond is in a water molecule

covalent bond

The symbol and charge for an electron

e-

Location of an electron in an atom

electron cloud

The chemical behavior of an atoms depends on the ability of a subatomic particle to move. Which one particle does this>

electrons

Where is a hydrogen bond found in water?

from a hydrogen atom of one water molecule to the oxygen atom of another water molecule

What does pH measure?

hydrogen ion concentration

The bond in NaCl

ionic

What is the pH of acid rain?

less than 5.6

What is the pH scale?

measures how acidic or basic a substance is (0-14)

polar molecule

molecule with an unequal distribution of charge, resulting in the molecule having a positive end and a negative end

The symbol and charge for neutron

no charge

location of neutron in an atom

nucleus

location of proton in an atom

nucleus

Which end of the water molecule is slightly negative?

oxygen end

The symbol and charge for a proton

p+

properties of water

polarity, cohesion, adhesion, excellent solvent, solid is less dense than liquid, high specific heat, can be found in nature as a solid, liquid or gas (only naturally occurring substance that is found in all three states)

The atomic mass is calculated by adding

protons and neutrons

What are the three subatomic particles?

protons, neutrons, electrons

What is NaCl

sodium chloride/ table salt

When the outer orbital is filled with electrons it tends to be

stable and nonreactive

Compound

substance formed by the chemical combination of two or more elements in definite proportions

capillary action

the combined force of attraction among water molecules and with the molecules of surrounding materials

Which subatomic particle makes each element unique?

the protons

Molecule

two or more atoms held together by covalent bonds

Ice is less dense than water because

water expands when frozen and ice floats on top of water.

What are buffers?

weak acids or bases that can react with strong acids or bases to prevent sharp, sudden changes in pH