Chem Final
A rare metal alloy is a superconductor at 55K. What is the temperature on the celcius scale?
-218C
How many photons of light are emitted when the electron in a hydrogen atom drops from energy level 3 to 1?
1
What does the ion phosphate contain?
1 phosphorus, 4 oxygen, to the third power negative
If 2.43g of Mg burns in air to produce 4.03g of MgO, what is the mass of reacting oxygen gas?
1.6g
What are the two unit factors that relate meters and millimeters?
1000 mm/1m and 1m/1000mm
One micro is:
10^-6/one millionth
If a rectangular A1 block measures 3.80 cm by 2.55 cm by 1.25 cm. What is tjhe volume of the rectangular solid?
12.2 cm3
Which is true about 60C
140F
4.51 x 3.6666 = _________
16.54
Calculate 2.76 x 6.63466 =
18.31
Mass of a proton is
1840 times mass of electrons
SI unit for volume is m3 which of the following is correct?
1L = 1000cm3
electron configuration for an atom of manganese
1s2 2s2 2p6 3s2 3p6 4s2 3d5
A piece of gold with 40g of its mass has a volume of 2cm^3, what is its density?
20 g/cm3
A piece of gold with 60g of its mass has a volume 2 cm3, what is its density?
30 g/cm3
how many neutrons are in the nucleus of an atom of copper-65?
36
numbers of significant figures in 060104 are:
5
How many significant figures are there in 0.00745610
6
the average of three measured lengths 6.64, 6.68, and 6.70 is:
6.67
Element X has two natural isotopes: X-63 (62.940 amu) and X-65(64.924 amu). Calculate the atomic mass of element X given the abundance of X-63 is 69.17%
63.55 amu
If a chemistry student weighs 155 lbs, what is the mass in kg?
70.4kg
Round off the following measurement to 3 significant digits: 726.8 mL
727 mL
The speed of sound in air is about 343 m/s. What is this speed in miles per hour?
767 mi/hour
A weather forecaster predicts the temperature will reach 31C, what is this Temperature in F?
88F
A weather forecaster predicts the temperature will reach 31C. What is this temperature in F?
88F
Which of the following is an example of quantized change in energy?
A ball rolling down a flight of stairs
Closeness of measurement is:
Accuracy
Which of the following of Dalton's proposals is still valid?
All of the above
What is the name of this chemical: NH4^+3
Ammonium
98F = _____C
Average of A and B
Which of the following describes a substance in the solid physical state?
B. the substance has a fixed volume C. the substance compresses negligibly
Which of the following is insoluble in water
BaSO4
What is CO3^-2
Carbonate
What is the smallest structure in this list that can be seen with an ordinary desk microscope?
Cell nucleus
What is the name of-- CrO4^ -2
Chromate
Water contains hydrogen and oxygen. Which of the following describes water?
Compound
Matter changing from liquid to gas is called?
Evaporation
Acetate can be shown as C2H3O2 or CH3COO-
False
An atomic molecule and cell molecule are about the same size
False
Which of the following metals react with sulfuric acid?
Fe
OH- can be described as which polyatomic ion?
Hydroxide
Predict the product from the following reaction: LiHCO3
Li2CO3, H2O, CO2
predict the product of Mg + O2 --> ________
MgO
Atoms combine to form:
Molecules
Which of the following statements is true?
Molecules are made of atoms
Which subatomic particle has a relative charge of 0 and a mass of 1 amu
Neutron
Dichromate are toxic substances that are usually insoluble in water. What is the formula for this polyatomic ion:?
None of the above
What is the max number of electrons that can occupy the 3rd energy sub level?
None of the above (d holds 10)
Which of the following is an example of chemical change?
Oxidation
Which of these is found in the nucleus of an atom?
Proton
the most stable allotrope of Sulphur is
S8
The matter has a fixed shape and volume with particles closely packed together with little movement
Solid
which arrangement of atoms is correct from low to high density
Sr, Mo, Ag
What is the different between sulfate and sunfite
Sulfate has one more oxygen than sulfite
Does SO3^-2 represent sulfate or sulfite?
Sulfite
which of the following is evidence for a chemical reaction
all of the above
when a neutral atom gains or loses electrons it becomes ___________
an ion
which of the following is true for both the orbit and an orbital
an orbit and an orbital represent a fixed energy state
Which of the following is part of Dalton's atomic theory?
atoms of the same element are alike in mass and size
The atomic radius tends to __________
decrease from left to right in periodic table
what particles form the outside fo an atom?
electron
which of the following discoveries led to the development of the quantum mechanical model?
electrons occupied different energy levels around the nucleus
ionization energy is the amount of energy required to add an electron in a ground state
false
anything that occupies space and has mass
matter
metalloids have some characteristics of __________
metals and nonmetals
When atoms bond together they form...
molecules
oxygen, sulfur, and selenium are ________
non metals
473F =
none of the above
Calculate 6.8/172.04
none of the above
Which is true about 78.3C?
none of the above
for all electromagnetic radiations:
none of the above
when the elements are arranged by atomic number, their ____________ properties vary periodically.
physical and chemical
Sugar dissolving in water is a ____________
physical change
Alpha rays are:
positively charged
the nucleus of an atom is:
positively charged and has a high density
which scientist proposed the idea of the "nucleus" after the unexpected results of his gold foil experiment?
rutherford
Matter changing from solid to a gas is called
sublimation
who was the first person to suggest the idea of electrons?
thomson
electro affinity is the energy change accompanying the addition of an electron to a gaseous atom
true
electrons can have specific energy value
true
nonmetals are dull and poor conductors of heat electricity
true
wave length is the distance between identical points on successive waves
true