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The following are the answers to [2024-2025 Review HW for Sig Figs, Fundamental Principles and Lab Safety].
Part 1
1) Emergency shower, front right corner of room (near USA flag), used when one gets chemicals all over their body/clothes.
Can not stop water from coming out once pulled handle down.(technically also when one's clothes are on fire but there are other faster way to put out clothes fires.
2) Safety glasses. They are in the Safety glass cabinet to the front left corner of the room (left of whiteboard when looking at them).
3) No eating while doing any lab. Notes: Unless stated, all labs are done on the benchtops, NOT ON TABLES.
Part 2
4) Kilogram
5) 100cm (or 1E2cm) = 1m or 0.01m (1E-2m) = 1cm
6) K (capital K not small case)
7) p (small case not capital)
8) mole (including the ending, "e", leaving "e" is the unit)
9) Kilo
10) 1X109nm (or 1E9nm) = 1m. or 1nm = 1E-9m
Part 3
11) observation
12) Precision is the "reproducibility" of a measurement (its focus is on the mechanics/process by how measurement is done).
13) Accuracy is about how close you are the desired outcome, not process of how you measurement (i.e. precision).
14) Qualitative observation are non-number based.
15) Not only do you want to give other people the desired outcome but also want to inform other of the measuring device to use (if not using same measuring device, will not get same results consistently).
16) In science, we use measuring device that have limitations on how accurate a measurement can get.
17) All know digits (0-9 is a digit) plus one guess
18a) Station A : ________________, Measurement ______________
18b) Station B : ________________, Measurement _______________
19) Zeros
20) 4 sig fig: 2 non-zero, 1 sandwich zero, and 1 trailing zero with last non-zero in decimal range. (zeros in front of 1st non-zero are never significant, Hint: put number in scientific notation).
21) 2.10X103g or 2.10E3g
Part 4
22) Electrons
23) Molecular compounds, covalent bond, molecule (there is another species that share electrons that we will deal with later in course).
24) Ionic compound, "Ionic bond" (does not really exists, more later), a set of ions.
25) Two types of ions (charged atom by losing or gain electrons) are: a) cations - atom lose electrons to form a positively charged ion and b) anion - atom gains electrons to form a negatively charged ion. Since they are a set, they stay together via Coulombic force (CF).
26) Kinetic Molecular Theory (KMT) say All substances are composed of particles that are in constant motion and sometimes interact/collide.
27) Matter and energy
28) Conservation of Mass - mass is neither created nor destroyed, must be conserved.
Conservation of Energy - energy is neither created nor destroyed, must be conserved.
29) Temperature is average kinetic energy (KE) of all the particles in a substance.
30) chemical change or chemical reaction, Intramolecular forces.
31) physical change, Intermolecular Force (IMF)
32) Empty space
33) At a given temperature, one "thinks" that all particles have the same amount of energy (since they are at the same temp, right? no not right).