What is the following measurements were made by a group of students using the same balance and a 25.00 gram weight regarding precision and accuracy
Trial Mass
1 23.96
2 24.01
3 23.98
4 23.97
Precise but not accurate
100
Write the symbol for the most common ion formed by sulfur.
S 2-
100
Given the reaction:
P4(l) + 6 Cl2(g) → 4 PCl3(l)
If the percent yield is 82%, what mass of P4 is required to obtain 2.30 g
PCl3 (Cl2 in excess)?
0.63 grams
100
What is the pressure in mmHg of 132 psi?
6820 mmHg
100
How much heat is absorbed by a penny from temperature of -8 C that increases to 37 C. Has mass of 3.10 grams and specific heat capacity: 0.385
53.7 J
200
What is the mass of a 468 mL sample of ethanol? The density of ethanol is 0.789 g/mL.
369 g
200
You have 3.26 mol of unknown gas with a mass of 143.5 g. What is molecular weight of the compound?
44.0 g/mol
200
Give example of an insoluble compound which contains Ag
AgCl, AgBr, AgI
200
Volume of 2.80 L at unknown temperature. When T = 0.00 C, the volume decreases to 2.57 L. What is the initial temperature?
25 C
200
If you inflate a balloon from a volume of 0.100 L to 1.85 L against external pressure of 1.00 atm, How much work is done? 101.3 J = 1 L* atm
-177 J
300
31.0 grams of the element phosphorus:
contain 31.0 moles of P
contain 6.02 × 1023 P4 molecules
contain 6.02 × 1023 P atoms
contain 31.0 × (6.02 × 1023) P atoms
contain 31.0 P atoms
6.02 * 10^23 atoms
300
What percent mass of chlorine is in CCl2F2?
58.64 %
300
What mass of ammonia can be produced from 15.0 kg each of H2 and N2? Answer in kg!
H2: 84.5 kg
N2: 18.2 kg
300
What is the volume when pressure is 1.37 atm for 0.845 moles at 315 K?
15.9 L
300
What is the relation between energy, wavelength, and frequency?
greater wavelength, lower frequency, low energy and vice versa
400
How many significant figures are in 128.113 + 526?
3
400
Which of the following names is INCORRECT?
H2SO3 sulfurous acid
CaH2 calcium hydride
Fe2O3 iron(III) oxide
SiO2 silicon oxide
NH4ClO3 ammonium chlorate
SiO2
400
W hich of the following is not a redox reaction?
A) MgSO4(s) → MgO(s) + SO3(g)
B) 4 Ag(s) + 2H2S(g) + O2(g) → 2Ag2S(s) + 2H2O(l)
C) 2 H2O2(aq) → 2H2O(l) + O2(g)
D) 2 NaBr(aq) + Cl2(aq) → 2NaCl(aq) + Br2(aq)
A) MgSO4(s) → MgO(s) + SO3(g)
400
The total pressure of 758.2 mmHg at 25 C when you college H2 gas. What is the partial pressure of H2 if the partial pressure of H2O at 25 C is 23.78 mmHg?
734.4 mmHg
400
Calculate the wavelength in nm emitted by frequency of 4.62 * 10^14
649 nm
500
What is the hypothetical element, Z? It has two stable isotopes.
Z-38 = 38.012 u 75.68%
Z-46 = 45.981 u 24.32%
The elementʹs atomic mass would be closest to which element?
Argon
500
What is the molecular formula for C2H3O which has a molar mass of 43.04 grams. Molecular compound has molar mass of 86.09 grams.
C4H6O2
500
What volume of 3.50 M H2SO4 s required to prep 250 mL of 1.25 M H2SO4?
89.3 mL
500
A sample of gas has a volume of 2.5 L at 30 °C and 720 mmHg. What will be the volume of this gas at 22 °C and 750 mmHg?
2.3 L
500
50 grams of water at 22 C is mixed with 125 grams of water initially at 36 C. What is the final temperature after mixing. Assume no heat lost to environment.