Science Midterm Day Two USE THIS ONE TERENCE!

small nuclei combine to form larger nuclei

#42 How does nuclear fusion create new elements inside stars?

conservation of entropy

#43 The equation for a chemical reaction must follow all of the following laws EXCEPT

symbols

#46 All of the following are examples of properties EXCEPT

2 1 2 6 6 1 6 2 3 2

Balanced equations: 2 H2 + 1 O2 = 2 H2O 6 CO2 + 6 H2O = 1 C6H12O6 + 6 O2 2 Fe + 3 Cl2 = 2 FeCl3

are related to the number of valence electrons

# 32 In a period of eight elements in the periodic table, the properties of those elements

polar bond

# 38 A bond between atoms where there is unequal sharing of electrons results in oppositely charged ends of the bond is called a

false, atomic number

#1 T or F The modern periodic table is organized according to atomic mass.

false, increase

#18 T or F When the temperature is constant, the volume of a gas will decrease as the pressure decreases.

its properties

#28 From an element's location in the periodic table you can PREDICT

the elements in a group

#31 Which has the same number of valence electrons?

H20

#35 Which of the following is covalently bonded?

covalent

#40 Bonds between atoms in which electrons are shared are called

mixtures

#47 Which type of matter consists of two or more substances that are NOT chemically combined?

it is made of substances that keep their individual properties

#48 Which of the following is NOT true of a compound

MAss

#52 The measurement of how much MAtter an object contains is its

numbers to correct

1, 18, 28 31, 32, 35, 38 40, 42, 43, 46, 47, 48, 49 52

endothermic; it absorbs energy

A chemical ice pack utilizes a chemical reaction that feels cold. This type of reaction is called -------- because it --------.

Molecular Compounds

Bonds are formed based on shared pairs of electrons form individual molecules atoms form a specific number of bonds based on unpaired electrons a polyatomic ion

see picture. it is a covalent bond and it is polar because the nucleus of Oxygen is larger and is pulling the hydrogen

Draw an electron dot diagram for hydrogen and oxygen

remains the same

During the time it takes for an entire sample of a substance to change from a solid to a liquid, the temperature of the substance

The periodic table is organized in groups and periods by the atomic number. It makes a pattern and goes from metals to nonmetals. By looking at the table you can tell what the properties are by the group or period the element is in.

Explain how an element's properties can be predicted from its position in the periodic table.

Nuclear Fusion happens in the stars to make new elements because on Earth we don't have the high temperature and the high pressure to make the nuclei collide.

How do elements with smaller nuclei form heavier elements in the stars? Why does this process occur naturally in stars but not on Earth?

surroundings to the ice

Ice melts as a result of thermal energy flowing from the

It would be a chemical change because they were forming new substances.

If the particles in a mixture were to break apart and then reconnect in different ways would that be a physical change or a chemical change?

For the chart:

Protons + neutrons = atomic mass Atomic number = number of protons number of protons = number of electrons Silicon: Atomic # 14, Protons 14, Electrons 14, You can't figure out the Neutrons or the atomic mass from this chart.

The balloons will deflate if you take them outside in the cold. This is Charles' Law. It means if the temperature decreases then the volume will decrease.

Suppose you buys some inflated party balloons that ar at room temperature. What will happen to those balloons if you take them outside on a very cold day? Explain.

pressure

The force or outward push of a gas divided by the area of the walls of the container is the gas's

picture of mixture and compound

The mixture is all different kinds of substances and the compound is pure. It is made of one kind of substance.

It must be testable by observation or experiment

What characteristic must be true of a good hypothesis?

It is well tested and explains a wide range of observations.

Which sentence best describes a scientific theory?

gas

Which state of matter undergoes changes in volume most easily?

If all scientists all over the world use the same measurements then they can share data and information.

Why is it helpful for scientists to use SI units when they record measurements?

Ionic Compounds

high melting and boiling points form crystals instead of molecules Component stick together based on electrical charge are electrically conductive when dissolved or melted may include both covalent and ionic bonds

volume

the amount of space that gas takes up is its