Atoms, Elements, Molecules, Compounds
atom arrangement
density and volume
state changes
conduction, convection
100
How many atoms in one molecule of sugar? The molecular formula for sugar is: C12H22O11
45
100
Are atoms bigger in hot water or cold water?
Neither! They are the same size! in hot water, the atoms are more spread out.
100
Determine the volume of a rectangular prism of length 2 cm, width 3 cm and height 4 cm. (no units, no credit)
24 cm^3
100
Describe the energy changes when a solid turns into a liquid and turns into a gas.
Least energy as a solid, most energy as a gas.
100
Since Canada is bigger it has more conduction and convection unlike the smaller New Zealand. Which country is better?
Canada, eh! (This question is a joke to tease Ms. Ferris. The question makes no sense!)
200
Which of the following is water (H2O)? (There may be more than one answer) Element Compound Molecule
compound and molecule
200
How are atoms arranged in a liquid compared with atoms arranged in a gas?
In a liquid, the atoms flow past each other and are connected by weak attractive forces. In a gas, the atoms have very little attraction to each other and fly around at really fast speeds!
200
The mass of an unknown object is 14 grams and its volume is 21 cm^3. Calculate its density and determine (and explain) if it can sink or float in whale oil which as a density of 0.925 g/mL. (no units means no credit!)
Density is 0.67 g/cm^3 Since the density is less than that of whale oil, it floats
200
When water condenses, describe what happens to the movement of the atoms.
The atoms slow down and are more attracted to each other. As a gas, there was less attraction and they would fly all over the place randomly. Now the atoms flow past each other slowly.
200
Give an example of convection in a gas.
wind
300
Which of the following is oxygen (O2)? (There may be more than one answer) Element Compound Molecule
Element Molecule
300
Compare the density of solid aluminum with the density of liquid aluminum. Describe the atomic structure of each.
Solid aluminum is more dense than liquid aluminum. The atoms of solid aluminum are closer together than the atom of liquid aluminum. The atoms in solid aluminum have a strong connection to each other and vibrate. Liquid aluminum atoms flow past each other.
300
Which of the following are true? Explain. A. Hot water floats on Cold water B. Cold water floats on Hot water C. Neither float on each other.
Hot water floats on cold water because it is less dense. The atoms are spread out farther apart.
300
Describe what happens to the atoms as you heat wax passes its melting point.
The atoms vibrate more and more until they break apart and flow past each other instead of vibrating in place.
300
You hold the end of a metal rod in hot boiling water. Describe what happens to the atoms which causes my hand to get hot.
The atoms on the end of the rod vibrate more and more vigorously. They bounce against atoms beside them causing them to vibrate more. This continues throughout the rod until the atoms in the rod start vibrating near your hand, causing your hand atoms to vibrate more feeling hot.
400
1. Which of the following is calcium (Ca)? (There may be more than one answer) 2. Which of the following is baking soda (NaHCO3) Element Compound Molecule
1. element 2. Compound and molecule
400
Compare the density of water at 4 degree Celsius with ice at -2.3 degree Celsius. Describe the atomic structure of each.
ice floats on water. Water molecules are closer together in water at 4 deg Celsius than ice. Water at 4 deg C is more dense than ice.
400
You have a graduated cylinder and a mass balance. Describe how you could determine the density of an irregularly shaped rock.
1. Place the graduated cylinder on the mass balance. 2. Zero the mass balance. 3. Add 50 mL of water. 4. Record the mass. 5. Place the rock in the cylinder. 6. Record the new volume. 7. The volume of the rock is the new volume - 50 mL
400
Why is it that you can get a worse burn from steam at 100 degrees Celsius than from water at 100 degrees Celsius? Explain in terms of energy transformations.
The steam condenses on your hand transferring its energy away from the steam. When it does that, the energy is transferred from the steam to your hand causing a lot of pain!
400
Describe what happens to the atoms in my finger when I touch ice. Describe what happens in terms of energy transformations.
When I touch ice, energy is transferred from my hands to my ice. The atoms in my finger do not vibrate as much causing my hands to feel colder.
500
Define the following terms: element compound molecule
Element: A substance entirely made up of ONE type of atom. Compound: a substance made up of two or more DIFFERENT elements. Molecule: Molecules are two or more atoms put together. The atoms can be the same or different.
500
Copper is more dense than aluminum. Describe 3 possible properties of copper's atoms that would lead to copper being more dense.
1. The copper atoms have more mass than aluminum atoms. 2. The copper atoms are smaller than aluminum atoms so more can fit in the copper. 3. The copper atoms fit together better than with aluminum atoms allowing more copper atoms to be in a particular space.
500
Determine the density of a rock if you know the following: mass of empty graduated cylinder: 23.4 grams mass of graduated cylinder with water: 45.8 grams mass of graduated cylinder with water and rock: 62.3 grams initial volume of water 48 mL volume of cylinder after rock was placed in it:63 mL
62.3 - 45.8 = 16.5 g density = mass/volume = 16.5 grams/(63-48) = 1.1 g/cm^3
500
Farmers spray fruit with water before a frost. Using energy transformations, explain why that stops the fruit from freezing.
When the temperature drops below 0 degrees Celsius, the water on the fruit begins to freeze. As it freezes, the energy is transferred from the water to the fruit causing the fruit to warm up. This makes sure the fruit does not freeze.
500
Describe the particle movement when water is being heated up on a stove. What is this method of heat transfer called?
When particles are heated, they speed up and move farther apart from each other causing the fluid in that area to be less dense and move up. The particles at the top are more dense (particles closer together) and sink to the bottom. As the particles float up, particles beside the area move in because their are no fluid atoms in that area. This makes a current called a convection current.
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