Lessons 5-7

Lesson 5

In lesson 5 we learned how to convert celcius to kelvin and vice versa. The equation for this is K=C+273 or C=K-273. We also learned about the properties of gas particles. The particles are in constant motion, traveling in a straight line that can only change direction when the particle hits another particle or wall. All the particles travel at different speeds. When the temperature increases the speed of the particles increase.

Practice Problems
1. Absolute zero is 0 degrees kelvin. It is a hypothetical temperature because it has never been reached.
7A. 373 degrees kelvin

Lesson 6

Lesson 6 talked about Charles Law, which states that in a gas, volume is proportional to temperature represented by a constant: k. When the temperature increases so does the volume but the density decreases. That is why hot air rises instead of falls.

Practice Problems

Lesson 7

Today we learned about weather fronts. In both cold and warm front there are clouds and a chance of precipitation. When cold air overtakes the warm air it is a cold front. When warm ait overtakes the cold air it is a warm front. These are pictured below.



Practice Problems
1. Hot air is less dense than cold air so it rises above cold air.
4. Colder weather with clouds and a chance of precipitation

Lesson 4

Today we did two different labs to learn about thermometers and how they work. Thermometers are generally made with alcohol or mercury; as the gases expand in the thermometer the levels increase and when the gas condences the temperature decreases. We learned that a melting point is the temperature where a substance melts or freezes, it can be either a solid or a liquid here. A boiling point is the temperature where a substance boils, it can be a liquid or a gas here. There are 3 temperature scales: Farenheit, celcius and kelvin. Below is a picture of the equation to covert celcius and farenheit.

Practice Problems
2. To construct a temperature scale you must first find the melting point and boiling point. After these are set it is easy to convert the other temperatures.
3. The celcius scale is based on 10 like the metric system, making it much easier to work with then farenheit. Boiling is 100 and melting is 0.

Unit Three: Lessons 1-3

Lesson 1

In lesson one we learned about weather, which is a state of atmosphere in a region over a period of time. Weather is the result of the interaction between Earth, water, the atmosphere and the Sun. There are many ways to describe weather and what it is doing.
Jetstream: High level in the upper atmosphere and moves across the U.S from west to east
Cloudcover: Areas covered by clouds
Fronts: Different waves of air, displayed on a line. Circles are warm and triangles are cold
Precipitation: Rain or snow

Practice Problems
2. A planet must have an atmosphere.
3. A physical change is when a substance changes forms, temperature, shape etc.

Lesson 2

Lesson 2 talked about proportions. Two variables are proportional when you can multiply the value of one by a constant to get the value of the other. When something is proportional the number that represents the 2 variables is represented by k. Volume increase is predictable. The height of rain is not dependant on the diameter of the container but the volume of rain is.

Practice Problems
3. The height will be the same but the volume will be different because the containers are different sizes.

Lesson 3

In lesson 3 we learned that density= mass/volume. The denisty of water is 1 gram per milliliter. Both snow and ice have densities that are less than water. If a substance changes phases it changes density.

Practice Problems
4. More because ice has a smaller density than water. When it melts the density increases so the volume would have to iincrease as well.
9A. Lead has a greater volume because it is more dense than iron.

Unit 1 Review

This unit in chemistry we learned a lot, from how theperiodic table is organized, to radioactive decay, to the structure of an element,to the types of bonds and how elements bond.

Lessons 6-10

                Inthese lessons we learned a lot about the periodic table. An element is abuilding block of matter and a compound is a pure chemical combination of 2 ormore elements in a fixed ratio. Each block of the periodic table represents anelement with the atomic mass and number, and chemical name and symbol. There isa picture below to describe this. Columns in the table are called groups androws are called periods. Elements in the same group have similar properties.

Lessons 12 and 13

                Thesesections talk about the structure of an atom. The nucleus is made of positivelycharged protons and no charge neutrons, which accounts for the mass of theatom. The number of protons is equal to the atomic number. Electrons are negativelycharged parts of the atoms that are away from the nucleus. In order for theatom to be neutral the charge of the protons and neutrons must equal zero. Anisotope is an atom with a different number of neutrons. We also learned aboutnuclear notation which is pictured below.

Lesson 15

                Thiswas the section where we learned about radioactive decay, alpha and beta aswell as fission and fusion. There is a picture below that illustrates alpha andbeta decay rather nicely. Fission is where a nucleus is split into otherparticles and fusion is where 2 nuclei join to form a larger nucleus.  Both release energy but nuclear fission canresult in nuclear chain reactions.

Lessons 18 and 19

                Inlesson 18 we learned about more about electrons. The period number of theelement equal the number of electron shells that element will have. The lastshell contains the valence electrons. All elements have noble gas envy, meaningthey want 8 valence electrons to become stable like the noble gases. Lesson 19talked about ions which are positively or negatively charged particles thathave lost or gained electrons. A cation has a positive charge and an anion hasa negative charge.

Lessons 20 and 22

                Inlesson 20 we learned that an ionic compound is made of positive and negativeions that are formed when metals and nonmetals combine. The order when namingthese is metal, nonmetal and –ide. There is a picture below that shows how tofigure out how many atoms of each element are needed to create a compound.Lesson 22 talked about polyatomic ions which are groups of atoms with anoverall positive or negative charge, usually anions. Below is a list of somehigh frequency ones.

Lesson 25 and 26

                Lesson25 talked about solubility and conductivity as well as the types of bonds. Thebonds are ionic, metallic, molecular and network covalent. The types of bondwill determine if the compound is soluble (capable of dissolving) or not(insoluble) and whether or not it will conduct before and after it dissolves.There are two pictures below that further explain the types of bonds.

We also learned about electron configuration and noble gasnotation. Both are shorthand ways of keeping track of an elements electrons andboth are pictured below.

Lesson 26

Today we learned about chemical bonds, which are attractions between atoms that hold them together in space. Different locations of the electrons in the bond account for different properties. There are 4 different types of chemical bonds: ionic, metallic and molecular and network covalent. There are some pictures to further explain these bonds and their properties.

This explains the four types of bonds and their properties

 

This shows what atoms can bond together and the bonds they form

 

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Practice Problems 1. The valence electrons are organized in such a way so that they hold each other up through their bonds. 3A. Metallic 3B. Network Covalent

Lesson 25

On Friday we did a lab to determine if different elements and compounds would conduct electricity to light a lightbulb. Each element of compound we tested we also tested when it was dissolved in water, however not all dissolved in water. From this lab we learned that in order to conduct electricity the element or compound had to contain some trace of metal. These are the patterns we came up with.

Substances that are soluble in water and conduct electricity have a metal element and one or more nonmetal elements.

Substances that are soluble in water and do not conduct electricity are made of hydrogen, carbon and oxygen atoms.

Substances that are insoluble and conduct electricity are metallic.

Substances that are insoluble and do not conduct electricity are made of non metal elements.

Practice Problems
1. Insoluble means that a substance does not dissolve in water.
3. That substance must have one or more metal elements because metal is a great conductor of heat and electricity.
6A. No, it is made of hydrogen, oxygen and carbon. None of those are metal elements so no electicity will be conducted.

Lesson 24

Today we learned about electron configuration, which is a shorthand way to keep track of all the electrons in their shells in an element. We also learned about electron shells and blocks in the periodic table. The table is divided into the S-block, D-block, P-block and F-block. Each block can only hold so many electrons in each of it's shells. the S block can hold 2, the d block can hold 10, the f block can hold 14 and the p block can hold 6. There is a diagram below that better displays this idea. There is also an example of electron configuration.



This is an exampke of electron configuration.



Practice Problems
2.Electron configuration is a shorthand way to keep track of all the placements of electrons in their shells in an element.
8.Thorium

Lessons 20-22

Lesson 20

In lesson 20 we learned that an ionic compound is composed of positive and negative ions formed when metals and nonmetals combine. We also learned the rule of zero charge. The negative and positive charges must total zero. Sometimes that means you need more of one element than the other so that the charges equal zero. There is a picture below that displays how this works and how to figure out how many atoms of each element you need.

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Practice Problems
2. If you know that you need a totalcharge of 0 then you know if one of your elements has a much higher charge than the other then you need more of the less charged atom.
3A. +1
3B. +3

Lesson 21

In lesson 21 we reinforced the rule of zero charge and learned that the total number of electrons in a compound must equal eight or a multiple of eight. We also learned about noble gas envy. Noble gas envy is the idea that all elements want to be stable like the noble gases and have a full valence electron shell. The elements must form bonds to complete these goals.

Practice Problems
3A. Yes because lithium has a charge of +1 and chlorine has a charge of -1 so they equal zero.
3B. No because lithium has a charge of +1 and chlorine has a charge of -1, but since there are 2 chlorine atoms the bond can't form because it doesn't follow the rule of zero charge.

Lesson 22

Today we learned about polyatomic ions which is a group of atoms with an overall positive or negative charge that are usually anions. There is a picture below that shows examples and names some high frequency polyatomic ions.

Practice Problems
1. A polyatomic ion is an ion that has 2 or more elements
3B. Potassium sulfate
3D. Magnesium carbonate

Lessons 17-19

Lesson 17

On Friday we did a flame test, which is a test done to see if there is a presence of metal atoms. We dipped rods in different chemical compounds and stuck that in a bunsen burner and made notes on the colors and patterns we saw. For the color to change we needed light energy. That is created when an excited electron moves to the next shell of an atom. When the electro moves back to it's original shell light energy is produced.

Practice Problems
1. Groups in the periodic table have similiar properties which means they turn certain colors. When performing a flame test if you see a color you can look on the periodic table and make connections to the elements that produce a similiar color to find out what it is.
4. I think it will be a yellow-orange because other compounds that contain sodiu are that color.


Lesson 18

In lesson 18 we learned more about electrons. The period number in the table is equal to the number of shells required to hold that elements electrons. And the group number is equal to the number of valence electrons that element has. We also learned that core electrons are all the electrons except the valence electrons.

Practice Problems
2. An elements group tells you how many valence electrons it has. If the element is neutral then it will have the same number of electrons as protons, allowing you to arange the electrons in shells of 2, 8, 8, or 18 if the element is after the transition metals.
3. They all have 2 valence electrons.


Lesson 19

In this lesson we learned about ions. An ion is an atom with a positive or negative charge because of lost or gained electrons. A cation is an ion with a positive charge and an ion with a negative charge is called an anion. Superscript denotes the charge of an atom. We also learned that metal atoms transfer electrons to nonmetals when they form compounds.


Practice Problems

1. An anion is an ion with a negative charge and a cation is an ion with a positive charge.
2. Noble gases have a full valence shell and are unreactive. The other elements are "jealous" because they too want that full shell.

Lesson 16

We learned more about nuclear equations. Nuclear equations explain what happens to elements after they undergo alpha decay, beta decay and fusion. New elements are created through radioactive decay, fission and fusion. Nuclear fission can result in nuclear chain reactions. For an example of these equations there's a picture below.

Practice Problems

Lessons 13 and 15

Today in chemistry we learned about isotopes and nuclear notation. Isotopes are variants of the one element. The element will have the same number of protons but can have different numbers of neutrons. We also learned about nuclear notation, which is the different ways writing an element's isotope. There are two ways to write it which are pictured below. In lesson 15 we learned about alpha and beta decay. Alpha decay occurs when an element loses 4 protons and 2 neutrons (helium) to become more stable. Beta decay is when in an attempt to become more stable a neutron turns into a proton and then loses and electron. Both types of decay emit energy.







Lesson 13 Practice Problems

1. Atomic number is the number of protons that are found in the nucleus of an element. Atomic mass is the number of protons plus the number of neutrons found in the nucleus.
4A. If the atom has no charge then, 9 protons, 12 neutrons and 9 electrons
6A. 30.7973
6B. 15
6C. I would say the most common isotope would be P-31 because that is the closest whole number to the average atomic mass.

Lesson 15 Practice Problems
4. The mass of an atom changes when an alpha particle is emmited because it loses 2 protons. Protons and neutrons make up the mass of the atom so if two protons are lost the mass will shrink.
5. When a beta particle is emmited the mass of an atom does not change because a neutron simply becomes a proton. A neutron is "lost" but a proton is gained so the total mass does not change. An electron is lost but they do not count for mass so it does not affect the mass of an atom.

Atomic Number and Mass

Today we learned about atomic numbers and masses. The atomic number is equal to the number of protons in the nucleus. The mass of an atom is made from the protons and neutrons in the nucleus. The average atomic mass is found by the subtracting the number of protons from the atomic mass and rounding. Electrons are the outside the nucleus and are not included in the mass.

Practice Problems
1. The atomic number is the number of protons in the nucleus.
3. Magnesium
5. Carbon has a larger atomic mass than Boron because it has more neutrons the boron, making the mass heavier.

Lessons 6-10

In class on Friday we learned that matter cannot be created or destroyed. The next main point was the periodic table. We learned how it was organized, such as elements in each column (Period) have similiar properties and what the writing in each idividual box meant. Atomic number, atomic mass, so on and so forth. There is a picture that represents this below. To help understand these similarities we did an activity where we organized the periodic table using cards which listed each element's atomic mass and number, reactivity and phase at room temperature. This helped to understand the placement of each element.




Chapter 6 Practice Problems
1. Describe the difference between an element and a compound.
An element is a building block of matter that can not be brokendown any farther by chemical means. A compound is a pure chemical combonation of two or more elements in a fixed ratio.
3. What is the difference between NaOH(s) and NaOH(aq)?
NaOH (s) is a solid and NaOH (aq) is aqueous, meaning that it dissolves in water.

Chapter 7 Practice Problems
1. What is a chemical reaction?
A chemical reaction takes place when one substance is made into another by adding liquid or heating it. Evidence of chemical reactions include color change and gaseous substances.
5A. Vinegar is a liquid and baking soda is a gas so the combonation of the two creates a liquid and carbon dioxide gas.
5B. Yes, a chemical change occurs because the substances start as a liquid and a solid and end as a gas and a solid.
5C. The sodium starts in baking soda and then dissolves into the liquid.

Chapter 9 Practice Problems
1. Reactivity,size and valence electron number.
2. Carbon and Silicon are more similiar than Nitrogen and Oxygen because carbon and silicon are in the same family whereas nitrogen and silicon are not.
5A. CaSO4
5B. The sulfer would be because it has a higher mass than oxygen.

Chapter 10 Vocab:

Atomic Mass: mass of a single element
Atomic Number: number of protons in an element's nucleus
Reactivity: describes whether or not an element will combine with other substances and the speed at which it takes place
Group: vertical column in the periodic table
Period: horizontal row in the periodic table
Alkali Metals: elements in Group 1A
Alkaline Earth Metals: elements in Group 2A
Halogens: elements in Group 7A
Noble Gases: elements in group 8A, non reactive
Main Group: 1A to 8A
Transition Metals: 1B to 8B
Lanthanides and actinides: two rows places seperately at bottom of table

Practice Problems
1. Reactivity increases as you go down group 1A (Alkali metals)
2. Radium and Barium
6. A, B, D, E