HTHS 1110 Unit 2

Polar molecules like H2O have ___ bonds between H and O.

Polar covalent

Kalium

Potassium

K

Potassium 19

Rn

Radon 86 (noble gas)

In human systems the three most common electromagnetic elements

Oxygen, Nitrogen, & Sulfur

why radon gas is a problem in homes.

*Radon is a radioactive gas that seeps up from the ground and diffuses into the air. * People who inhale high levels of radon are at an increased risk of developing lung cancer. It is the second leading cause of lung cancer in the U.S. * Radon levels can be higher in homes that are well insulated (the gas can't escape) and are built on soil rich in uranium, thorium, and radium. * Basements and first floors have the highest radon levels (closest to the ground) * Testing is the only way to know if elevated radon levels are in a home.

Nuclear rearrangement

- nuclei becomes excited - loses its energy - gamma radiation - this is where protons and neutrons rearrange themselves in a lower-energy configuration - the "leftover" energy is released as a photon

isotopes

-Atoms with the same number of protons but different numbers of neutrons -Some are stable -Isotopes that are unstable are radioactive -Radioisotopes can be used as tracers or markers in chemistry and medicine and can be used to kill cancer cells.

Noble gases usually don't react with other elements. Why? (More than one answer may apply).

-Noble gases don't need to donate, accept, or share electrons to fill their valence shell. Because their highest orbital shell is filled, the electrons are happy. -They have a filled valence shell This means noble gasses have a valence of 0. They are perfectly content and don't need to interact.

A chloride ion has a charge of ___. It has 17 protons and 18 electrons

-1

Electron rearrangement

-different orbitals have different amount of energy -if an electron shifts from a higher-energy to a lower-energy orbital the "leftover" energy is released as a photon

mass of electron

0 amu

Match the subatomic particle to its mass in Daltons (or atomic mass units or amu) Positron (antielectron)

0.0005 Da

What is the subatomic particle to its mass in Daltons (or atomic mass units or amu) Electron

0.0005 Da

What is the subatomic particle to its mass in Daltons (or atomic mass units or amu) Protons

1.007= Da

What is the subatomic particle to its mass in Daltons (or atomic mass units or amu) Neutrons

1.009= Da

mass of proton

10^-27 kg (1 a.m.u)

A sodium atom is neutral (uncharged). It has 11 protons and ___ electrons.

11

This is a Wikipedia definition of a Dalton (unified atomic mass unit). The Dalton or unified atomic mass unit is a unit of mass widely used in physics and chemistry. It is defined precisely as 1 1/2 of the mass of an unbound neutral atom of carbon-12 in its nuclear and electronic ground state at rest. Based on this definition, what is the mass (under the specified conditions) of a 12C atom?

12 Da

A potassium ion has a charge of +1. It has 19 protons and ___ electrons. Answer with a whole digit (interger) with no spaces or decimal.

18 Here's how we set up that problem: 19 protons are 19 packets of positive charge (+19). An unknown number of electrons are as unknown packets of negative charge (-x). The total number of positive and negative charges is +1. +19 - x = +1 x = 18

exergonic reaction

A spontaneous chemical reaction in which there is a net release of free energy.

Ionic bond (In)

A bond where there is a transfer of electrons between atoms (found in rows 1 & 2)

Covalent bond

A bond where two atoms share their electrons ( usually between 2 non-metal elements )

Base definition

A compound which breaks apart in water to form OH- or a compound which acts as a hydrogen ion acceptor

Polar covalent bond

A covalent bond in which electrons are not shared equally

endergonic reaction

A nonspontaneous chemical reaction, in which free energy is absorbed from the surroundings.

positrons

Are like electrons in all respects except they carry a positive charge

Ar

Argon 18 (noble gas)

Ion

An atom or group of atoms that has a positive or negative charge.

Be

Beryllium 4

B

Boron 5

Br

Bromine 35

P

Phosphorus 15

Ca

Calcium 20

C

Carbon 6

Electrons are

Chemistry

Cl

Chlorine 17

When ice melts, the ice absorbs heat from the environment. This is what type of reaction?

Endothermic reaction, ice absorbs the heat from the environment. This is an endothermic reaction.

Characteristics of the solvent

Effect the diffusion rate

Electrons spend relatively more time closer to the oxygen atom in a water molecule because oxygen is:

Electronegative

A reaction when you use a hand warmer

Exothermic reaction (when energy is added in the form of oxygen which reacts with the iron powder in the hand warmer, releasing energy in the form of heat.

F

Flourine 9

He

Helium 2 (noble gas)

A___ temperature increases the diffusion rate.

High

Diffusion means substance travel from:

High concentration to low concentration

What does not change when a substance undergoes a state change?

Mass

Ionic bonds have

Melting and boiling points that are high Normally solids Don't have a definite shape

___ bonds are what give water its special properties.

Hydrogen

H

Hydrogen 1

O

Oxygen 8

I

Iodine 53

Ferrum

Iron

Fe

Iron 26

Heating and cooling create changes in states. Why does heating cause state changes?

It causes attractive forces between molecules to break.

Kr

Krypton 36 (noble gas)

Li

Lithium 3

Distance effects the diffusion rate

Longer distance slows the rate

Mg

Magnesium 12

Ne

Neon 10 (noble gas)

N

Nitrogen 7

Se

Selenium 34

Si

Silicon 14

Which has an easier time moving through the cell membrane?

Small, non-polar molecules

Natrium

Sodium

Na

Sodium 11

fluorine>oxygen>chlorine>nitrogen>bromine>sulfur

The most electronegative elements are:

Double covalent bonds are

Strong but weaker that triple covalent

Ionic bonds are

Stronger than hydrogen bonds, but weaker than covalent bonds

Triple covalent bonds are

Strongest

S

Sulfur 16

Technetium

Tc 43 Only element between atomic numbers 1-83 that does not occur naturally on Earth. (43 protons + 56 neutrons = 99)

Potential energy that drives passive transport (diffusion). What is the source of potential energy?

The concentration gradient

What doesn't change when a substance under goes a state change

The mass of the substance

What is the reason evaporation only occurs at the surface is that

The molecules get enough energy to become gaseous due to collisions with molecules in the atmosphere.

In Polar molecules, there is ___sharing of electrons among atoms.

Unequal

What are the three main states of matter on earth?

Water, liquid, gas

Sublimation

When molecules go directly from a solid to a gaseous state, this is called

Xe

Xenon 54 (noble gas)

Anion

an ion with a negative charge

Cation

an ion with a positive charge

A chloride ion with -1 charge is an

anion (negatively charged ion)

How is liquid carbon dioxide made?

by subjecting carbon dioxide (CO2) to very high pressure

4 most common elements

carbon, hydrogen, oxygen, nitrogen

A sodium atom is an ion (charged). It has 11 protons and 10 electrons. A potassium atom is an ion (charged). It has 19 protons and 18 electrons. These sodium and potassium ions are:

cations (positively charged ions)

What is the subatomic particle location within the atom electron

cloud of probability outside the nucleus

nuclear fission energy

comes from changes to the atom's nucleus: when the nucleus of an atom divides (coming apart) -When nuclei split apart, large amounts of energy -some of this energy is released as photons -nuclear bombs are pretty bright for this reason

Ions are

electrons

Frozen water (ice) is _____ dense than liquid water.

less

Single covalent bonds are

long and weak stronger than ionic

What is the subatomic particle location within the atom neutron

neclues

What is the charge of the subatomic particle electron

negative

Isotopes are made when we manipulate

neutrons

What is the subatomic particle location within the atom proton

nucleus

What is the charge of the subatomic particle positron (antimatter electron)

positive

"p"H in pH

power of hydrogen concentration high pH cannot accept as many hydrogen atoms, low pH has the ability to accept more

unstable isotopes

radioactive, also known as radioisotopes

What is a neutron's mass?

similar to protons (1 a.m.u)

Hydrogen bonds are

weak

ion

when the number of electrons is no longer equal to the number of protons

What is the charge of the subatomic particle neutron

zero (no charge)