1
What is the smallest unit of matter?
Atom
Are homogenous mixtures mixed evenly or not evenly?
Evenly
True or false: Compounds can only be broken down through chemical reactions
True
True or false: atoms of silver (Ag) and gold (Au) are the same
False
What is the chemical abbreviation for potassium?
K
What is the name for 2 or more atoms held together with chemical bonds?
Molecule
True or false: all molecules are compounds
False
(Refer to picture 2) What type of mixture is this?
What role do protons, neutrons, and electrons play in atoms?
Protons - positively charged
Neutrons - no charge
Electrons - negatively charged
What is the difference between ionic and covalent bonds?
Ionic - giving up
Covalent - sharing
Are elements pure substances, compounds, or mixtures?
pure substances
If there is only a change in color in a substance, is it a physical or chemical reaction?
Physical reaction
What are columns on the periodic table called?
Groups/families
What are rows on the periodic table called?
Periods/series
When amino acids are joined together, what bond does this create?
Peptide bond
Are compounds pure substances or mixtures?
Pure substances
(Refer to picture 1) What type of chemical bond is this?
Ionic bond
What is group 18 on the periodic table called, and why?
Noble gases, they are stable and do not easily react
How many TOTAL electrons can be held in the first three energy levels (shells)?
2+8+18 = 28 total electrons
What group(s) does hydrogen not typically bond with?
Metals (alkali, earth, etc)., noble gases
What does the Law of Definite Proportions say?
A given chemical compound always contains the same elements in the exact same proportions by mass
Rubidium (Rb) has 37 protons and an atomic weight of around 85. How many electrons and neutrons does it have?
37 electrons
48 neutrons
What is an isotope?
An isotope is a variation of the element, with the same number of protons but a different number of neutrons
Zinc (Zn) has 30 protons and an atomic weight of 65.38. How many electrons and neutrons does it have?
35 neutrons
30 electrons
When sugars are joined together, what type of bond is this?
Glycosidic bond