Matter
What are the 3 main states of matter? What are the main distinctions between them from the perspective of chemistry.
Solid: Atoms are very tight together, generally have a harder time changing shape
Liquid: Atoms are less close together, move more easily
Gas: Atoms are very far away from eachother, fill up the entire space they occupy
Where are protons, neutrons, and electrons located?
Protons and neutrons are located within the nucleus, whereas electrons orbit outside of the nucleus.
Give the percent composition of Hydrogen and Chlorine in HCl
H: 3%
Cl: 97%
Give the electron configuration of lithium
1s22s2
What are ions?
Grinding sugar into powder is an example of a (chemical/physical) change
Physical
What are the charges of protons, neutrons, and electrons?
Protons have a charge of +1, electrons have a charge of -1, and neutrons are neutral.
Find the percent composition of CuBr2
Cu: 28.45%
Br: 71.55%
Give the electron configuration of carbon
1s22s22p2
Positive ions are called ___ions while negative ions are called __ions
Cations, anions
Explain homogenous vs. heterogenous mixtures. Give examples for each.
Homogenous mixture: uniform throughout.
Heterogenous mixture: not uniform.
How much do protons, neutrons, and electrons weigh?
Protons and neutrons both weigh one AMU, whereas electrons weigh almost nothing.
Find the percent compositions of sodium, oxygen, and hydrogen in this compound: NaOH
Na: 57.48%
O: 39.99%
H: 2.53%
Give the condensed electron configuration of calcium
[Ar] 4s2
Positive ions have (more/less) electrons than neutral atoms, while negative ions have (more/less) electrons than neutral atoms.
Less, more
Cooking chicken in the oven is an example of a (physical/chemical) change
An atom contains 3 protons, 3 neutrons, and 3 electrons. What is its atomic number?
3
Give the percent composition of the elements in Mg(NO3)2
Mg: 16%
N: 19%
O: 65%
Give the condensed electron configuration of iodine
[Kr] 5s24d105p5
Group 15 elements have a charge of __
-3
What is the difference between a compound and a mixture. Give an example of each.
Compounds are pure and can only be separated by physical means. Mixtures are impure and can only be separated by chemical means.
An atom contains 3 protons, 3 neutrons, and 3 electrons. What is its mass number?
6
Give the percent composition of elements in Al2(SO4)3.
Al: 16%
S: 28%
O: 56%
Give the condensed electron configuration of a Ca+ cation.
[Ar] 4s1
Define isoelectronic and give an example of 2 elements or ions that are isoelectronic.
Atoms or ions that have the same electron configuration.