Elements & Periodic Table
What element does the prefix "hydro-" suggest?
hydrogen
The formula for salt is NaCl. What two elements make up salt? How many atoms are in one molecule of salt?
sodium and chlorine; 2 atoms
physical
What is a solute?
something of lesser quantity in a solution; the thing being dissolved
What is another word for stirring?
agitation
How many atoms are in the chemical formula H6C12O6?
24
Which of these is not an element?
a. Na
b. Br
c. Pb
d. OH
OH. This is a compound of oxygen and hydrogen
Mr. Soto's car sits outside in the rain for several days. Afterwards, he notices some orange colored substance collecting on parts of the car. Is this a physical or chemical change?
chemical; rust
any solution in which the solvent is water
What is the difference between a heterogenous and homogenous mixture?
heterogenous mixtures are not evenly distributed; homogenous mixtures are evenly distributed and difficult or impossible to separate
What does the atomic number of an element represent (number in the top left or top middle)?
number of protons in one atom of an element
Count how many atoms are in the formula: O3HeFe6
10
Mr. McBride left some apples in his fridge for 3 weeks. When he goes to grab one, he notices it's a different color. It also smells different. Is this a physical or chemical change?
chemical; rotting
Think back to our Koolaid Lab. Were you making the mixture in Beakers B and C more or less concentrated?
less concentrated
There is 30g of sugar in a 0.2L cup of coffee. What is the concentration of sugar in the coffee cup in g/L?
150 g/L
What does atomic mass represent? (What makes up an element's atomic mass?)
protons plus neutrons
Give the number of atoms for each element in this chemical formula:
Br6(Ra2P)3
6 bromine, 6 radon, 3 phosphorus; 15 total
A car uses gasoline to move. Is this a physical or chemical change?
when there is not enough solvent to dissolve the amount of solute
What are the three Effects on Dissolution?
agitation, temperature, surface area
sharing electrons
Your muscles use glycogen to move. Glycogen is a form of energy converted from glucose to be used by the body. Is this a chemical or physical change?
chemical
If you add more solute to a saturated solution, what will happen? Explain.
it will become oversaturated; no more solute can be dissolved unless there is something else affecting the solution
heat up the tea