Chemistry Final Test 1
The chief advantage of the metric system over other systems of measurement is that it
is in multiples of 10
What is not an example of matter? air, light, gas, Carlos and Clarita
light
The sum of the protons and neutrons in an atom equals the
mass number
All atoms are
neutral with the number of protons equalling the number of electrons
isotopes of the same element have different
numbers of neutrons
The atomic number of an element is the total number of which particles in the nucleus
protons
The particles that are found in the nucleus of an atom are
protons and neutrons
What is a physical change
some properties of the material change but the composition is still the same
What does the 84 in the name krypton 84 represent
the mass number
The mass number of an element is equal to
the total number of protons and neutrons in the nucleus
T or F: The mass of a neutron nearly equals the mass of a proton
true
In what ways are two isotopes of the same element different. Explain why isotopes have the same chemical behavior
two isotope son the same element have different amounts of neutrons, but he numbers of protons and electrons are the same so they have the same chemical behavior.
The quantity of 44 liters expressed in cubic meters is
0.044m³
What is the quantity of 0.00075m expressed in centimeters
0.075cm
What is the density of an object having a mass of 8.0g and a volume of 25cm³
0.32g/cm³
What is the quantity of 987 milligrams expressed in grams
0.987 grams
If E is the symbol fir an element, which 2 of the following symbols represent isotopes of the same element? 1. 20/10 2. 20/11 3. 21/9 4. 21/10
1 and 4 (the bottom number which is number of protons has to match)
What is the volume of 80.0g of either if the density of either is 0.70g/ml
1.1*10²
The diameter of a carbon atom is 0.000000000154m. What is the number expressed in scientific notation
1.54*10⁻¹⁰m
What is the relative mass of an electron
1/1840 the mass of a hydrogen atom
Calcite the number of neutrons in lead-212
130
preform the following operation make sure your answer has the correct number of significant figures. 3.430*5.2
18.0
Which of the following elements ha the same amount of neutrons as phosphorous 31?
31 is the mass number so do 31- 15 the atomic number and you get 16 so the answer is 32/16S
How many protons, neutrons and electrons does an atoms with the atomic number 50 and a mass number of 125 contain
50 protons 50 electrons 75 neutrons
The element chromium od 4 naturally occurring isotopes. Use relive abundance of each to calculate the average atomic mass if chromium.
52
An element has the atomic number 76. The number of protons and electrons in a neutral atom of the element are
76 protons and 76 electrons
List the number of protons, neutrons, and electrons in ²⁰F
9 protons, 9 electrons, 11 neutrons
What is not a physical property of matter? mass, color, melting point, ability to rust
ability to rust
Which of the following cannot be classified as a substance? air, salt, nitrogen, gold
air
What unit is used to measure weighted average atomic mass
amu
As a consequence of the discovery if the nucleus by Rutherford which model of the atom is though to be true
Electrons are distributed around the nucleus and occupy almost all the volume of the atom
The smallest particle of an element that retains the properties of an element is an
atom
A golf ball has more mass then a tennis ball because it
contains more matter
Which is not a physical property of water? it has a boiling point of 100°C, It is colorless, It is composed of hydrogen and oxygen, sugar dissolves in it
It is composed of hydrogen and oxygen
A cube of gold colored metal with a volume of 59cm³ has a mass of 980g. The density if pure gold is 19.3g/cm³. Is the metal pure gold
No because the density if this gold if 16.61g/cm³ and that does not match the density of real gold
The weight of an object
depends of its gravitational field
What is a chemical change
The composition of the material always changes and there is a transfer of energy, or change in color, or production of gas, or formation of a precipitate.
Chlorine has 2 naturally occurring isotopes Cl35 and Cl37. The atomic mass of chlorine is 36.45. Which of these 2 isotopes of chlorine is more abundant
The isotope Cl37 because 37 is closer to 36.45 then 35
Which of the following is a physical change? corrosion, evaporation, explosion, rotting
evaporation