True or False? Electrons are embedded in a positively charged sphere.
False
True or False- The periodic table arranges elements with similar properties into columns.
True
I am an atom that has lost one electron. Do I have a positive or a negative charge?
Positive
What kind of mixture is a solution? Spell it.
Homogeneous mixture
What is another name for Thomson’s atomic model?
Plum-pudding model
What do elements share or transfer to form compounds?
Electrons
If I am an atom with a positive charge, do I have more protons than electrons, more electrons than protons, or the same amount of each?
More protons than electrons
What is an aqueous solution? Give an example.
A solution in which the solvent is water.
Example: coffee, tea... many possible answers.
What experiment led a scientist to conclude that an atom is mostly empty space?
Gold foil experiment
How do compounds and elements differ?
Elements have one kind of atom; compounds have different kinds of atoms.
It is very unlikely you will find me in the form of an ion. Which group on the periodic table am I in, and what am I?
Group 8 (noble gas)
What does concentration mean, and what are the units when we use the formula C=m/v?
Concentration is the amount of solute in a solution.
m is in g, v is in mL, C is in g/L
What charge do cathode rays have?
Negative charge
True or false? Valence electrons are found in the innermost shell of an atom.
False: they are on the outermost shell
How many electrons does nitrogen want to gain or lose as an ion?
Nitrogen wants to gain 3 electrons.
What is 1 ppm equal to, and what does ppm stand for?
1 ppm = 1 mg/L
ppm stands for parts per million. It is a unit of concentration.
The center of every atom and contains at least one proton. (Spell it.)
Nucleus
Which atomic model representation shows ONLY the valence electrons? Draw it for chlorine.
Lewis notation
Which elements on the periodic table follow the duet rule... and what is it?
Li and Be.
The duet rule explains how lithium and berrylium want to be stable like the nearest noble gas to them, helium - it has only two valence electrons.
What is the octet rule?
The tendancy for elements to acquire the electron configuration of the noble gas nearest to them on the periodic table.
A saline solution that is used to dissolve drugs is 0.92% (m/v) NaCl in water. How many grams of NaCl are required to prepare 35.0 mL of normal saline solution?
Show your work on the board, with all the steps and correct units.
0.32 g