PROPERTIES AND CHANGES
SORTING MATTER
READING THE TABLE
REACTIONS AND EQUATIONS
ACIDS AND BASES
FINAL JEOPARDY
100
Color, hardness and melting point are all this kind of property. You can observe them without changing what the substance is.
What is a physical property?
100
Made of only one kind of atom, and it cannot be broken down by a chemical change. Name this type of matter.
What is an element?
100
The elements in the far-right column of the periodic table. Their outer shell is already full, so they barely react with anything.
What are the noble gases?
100
In a chemical equation, the substances written on the left of the arrow have this name.
What are the reactants?
100
Pure water sits at this number on the pH scale. Everything else is compared to it.
What is 7, which is neutral - not acidic?
200
Bubbles appear when water boils. Bubbles also appear when baking soda meets vinegar. Only one of those is a chemical change. Say which one, and say what the real test always is.
What is the baking soda and vinegar - and the real test is whether a NEW substance formed?
200
Salad, sand in water and granite are all sorted into this group, because you can see the different parts.
What is a heterogeneous mixture?
200
The elements along the staircase between the metals and the nonmetals. They have some properties of both. Name this group.
What are the metalloids?
200
The law that says the total mass of the reactants equals the total mass of the products.
What is the law of conservation of mass?
200
Dip blue litmus paper into an acid. Name the color it turns.
What is red?
300
The insect in the picture stands on a pond without sinking. Name the property of water that holds it up, and name the water-to-water attraction that causes that property.
What is surface tension, caused by cohesion?
300
In the picture, the small particles moving around the outside carry a charge of negative one and have almost no mass. Name them, and name the part of the atom that holds almost all of its mass.
What are electrons - and the nucleus holds almost all of the mass?
300
How many oxygen atoms in total are in 3 Ca(NO3)2?
What is 18?
3Ca(NO_3)_2\ \rightarrow\ 3 \times 2 \times 3 = 18\ \text{oxygen atoms}
300
You burn a log in an open fireplace. The ashes weigh far less than the log did. Say why mass was not destroyed, and say what would be different in a sealed container.
What is: carbon dioxide and water vapor left as gases and were never weighed - in a sealed container the mass would not change at all?
300
Lemon juice, vinegar and stomach acid. Say whether their pH is above or below 7, and name one other property they share.
What is below 7 - and they turn blue litmus red, or they can react with a metal to make a gas?
400
Water climbs up the inside of a plant stem. Water also beads into a droplet on a leaf. One of those is adhesion and one is cohesion. Say which is which, and say how you tell them apart.
What is: climbing the stem is adhesion, water sticking to a different material - beading into a droplet is cohesion, water sticking to water?
400
Salt water looks exactly the same all the way through, so a student calls it a compound. Say why that is wrong, and say what salt water actually is.
What is: nothing is bonded in salt water, so it is a homogeneous mixture - and it can be separated by physical means such as evaporating?
400
CO and Co are not the same thing. Say what each one is, and say what the second capital letter tells you.
What is: CO is carbon monoxide, a compound of carbon and oxygen - Co is cobalt, one element - and a second capital letter always starts a new element?
400
H2 + O2 makes H2O, but the equation is not balanced. A student fixes it by changing H2O to H2O2. Say what is wrong with that fix, and give the correct balanced equation.
What is: they changed a subscript, which makes a completely different substance - only coefficients may change, so the answer is 2H2 + O2 makes 2H2O?
2H_2 + O_2rightarrow2H_2O
400
An acid and a base are mixed together and the pH moves toward 7. Name this reaction.
What is neutralization?
500
A steel bolt sinks in water. Drop the same bolt into liquid mercury and it floats. Nothing about the bolt changed. Explain both results using density.
What is: density belongs to the material, not the piece - an object sinks in a fluid that is less dense than it is and floats in a fluid that is more dense, and steel is denser than water but less dense than mercury?
500
Two atoms are both carbon. One has 6 neutrons and the other has 8. Say what the two atoms are called, and say what would have to change to turn one of them into a different element.
What are isotopes - and you would have to change the number of protons?
500
Count every atom in 2Al2(SO4)3. Give the total.
What is 34?
2Al_2(SO_4)_3\ \rightarrow\ \4Al + 6S + 24O = 34\ \text{atoms}
500
Photosynthesis is 6CO2 + 6H2O + light energy makes C6H12O6 + 6O2. Count the oxygen atoms on each side, and say what your count proves.
What is 18 oxygen atoms on each side - which proves the atoms were only rearranged, so mass is conserved?
6CO_2,12O+6H_2O,6O=18rightarrowC_6H_12O_6,6O+6O_2,12O=18
500
One liquid has a pH of 3. Another has a pH of 5. Say which is more acidic, and say exactly how many times more acidic it is.
What is the pH 3 liquid, and it is 100 times more acidic - each whole step on the pH scale is a factor of ten?
500
A sealed plastic bag holds a cup of baking soda and a cup of vinegar side by side. You put the whole bag on a balance and write down the mass. Then you tip the cups together without opening the bag, and the bag puffs up. Say what the balance reads now compared to before, name the law that explains it, and say what would have been different if the bag had been left open.
What is: the balance reads exactly the same - the law of conservation of mass - and if the bag had been open the carbon dioxide would have escaped, so the mass would have appeared to drop?
\text{mass of reactants} = \text{mass of products}\ \ \text{(closed system)}