Chemistry L1-21 Quiz
How many neutrons does the most common isotope of hydrogen have?
0
A piece of pencil graphite (made of carbon atoms) has a mass of 0.12 grams. How many moles of carbon atoms are in the lead? (The molecular mass of carbon is 12 g/mol.)
0.01 moles of carbon atoms
What is the density of a solid that has a mass of 9.2 grams and a volume of 12.3 cm3 ? Would this object oat or sink in water?
0.75 g/cm^3 , float
An empty container has a mass of 62.000 grams. You fill it with 24.6 mL of a liquid. The final mass of the container is 81.34 grams. What is the density of the liquid to the correct number of significant figures? (density of the liquid = mass of the liquid divided by the volume of liquid)
0.786 g/mL
What is the mass of a liquid with a density of 2.12 g/mL and a volume of 53.0 mL (to the nearest gram)?
112 g
Which of these elements has the largest atomic radius? Bromine (Br), Silicon (Si), Magnesium (Mg), Astatine (At), Barium (Ba)
Barium (Ba)
Ocean water is a good example of a mixture because _____
the mixture of water and salt can be physically separated.
What is the correct electron configuration for an atom of sodium (Na)?
1s^22s^22p^63s^1
You performed paper chromatography on some marker ink and found that one of the pigments had a retention factor of 0.25. The total distance the solvent traveled was 8.0 cm. How far did the pigment travel?
2.0 cm
What is the condensation point of water?
212 degrees Fahrenheit
If you are driving at a speed of 55.0 miles per hour, then what is your speed in meters per second? (Hint: 1 mile = 1,609 meters.)
24.58 meters/second
One mole of aluminum atoms has a mass of 27 grams. How many grams are in 9.0 moles of aluminum?
243 grams
How many mL are in 3.4 L?
3,400 mL
The density of mercury is 13.6 g/mL. What is its density in lbs/L? (Hint: 1 lb = 0.454 kg)
30.0 lbs/L
A piece of copper wire contains 5 moles of copper atoms. What is its mass? (The molecular mass of copper is 63.5 g/mol.)
318 grams
Use dimensional analysis to convert 4 days into seconds.
345,600 seconds
How many significant figures are in 54,050?
4
How many valence electrons does silicon have?
4
What is the principal quantum number for the last electron that is added to potassium?
4
In which energy level is the outer electron in rubidium located?
5
A computer chip contains 1.20 x 10^23 atoms of silicon. What is its mass? (The molecular mass of silicon is 28 g/mol.)
5.6 grams
Simge's guinea pig weighs exactly 560. grams. Which of the following most accurately expresses the weight of Simge's guinea pig in scientific notation?
5.60x10^2
Which of the following is the closest to a mass of 500 mL of water?
500 g
The area of a rectangle can be found by multiplying its length by its width. What is the area of a rectangle that is 5.6 cm in length and 9.24 cm wide? Report your answer with the correct number of significant figures.
52cm^2
. What is the maximum number of electrons that can be found in a 5p cluster (or orbital) of a single atom?
6
A piece of aluminum foil has a mass of 27 grams. About how many atoms does this contain? (Aluminum has a molecular mass of 27 g/mol.)
6.02 x 10^23 atoms
Which of the following is a conversion factor?
60 seconds/1 minute
If you add 50.0 mL of water to a beaker containing 22 mL of water, then how much water do you have in the beaker?
72 mL
How many valence electrons does krypton have?
8
Pure substances are further divided into elements and compounds. Which one best describes the rust found on a vehicle over time?
A compound.
Which of the following causes condensation in water?
A decrease in temperature
Which of the following is the most heterogeneous mixture?
A pizza
Which feature of the evaporating dish makes it effective in the evaporation process?
A shallow bottom to increase the surface area of a liquid, leaving the solid behind.
Why did Democritus disagree with Aristotle?
Aristotle thought matter could be divided infinitely, but Democritus thought there were tiny, indivisible particles.
As you move from left to right on the periodic table, why does the atomic radius decrease?
As more protons are added, the more tightly the surrounding electrons are drawn inwards.
Why should you avoid looking directly at magnesium burning?
Because of the high energy released and the ultraviolet flame present.
As you move from top to bottom on the periodic table, why does electronegativity decrease?
Because the outermost electrons get farther and farther away from the atom's nucleus, the attraction between the nucleus and bonding electrons decreases.
Which two elements would have the most similar atomic radii? Beryllium and magnesium, Sodium and beryllium, Aluminum and carbon, Lithium and beryllium, Boron and silicon
Boron and silicon
If you need to dispense a precise amount of volume, which instrument would you use?
Burette
Which of the following is an example of a chemical change?
Burning a candle.
Which is the symbol for the element that contains six electrons in each of its neutral atoms?
C
Which element has a mass number of 12 and contains 6 neutrons?
Carbon
Which of the following was the instrument used for the discovery of the electron?
Cathode ray tube
Which of the following changes to sugar is an example of a physical change?
Dissolving it in coffee.
Alcohol and water are best separated from one another by:
Distillation
Which of the following would be best used for swirling and mixing liquids?
Erlenmeyer ask
Which is a way to separate solid sugar from a solution of sugar water?
Evaporation
Which element has the highest electronegativity?
Fluorine
Which of the following is the poorest conductor of electricity? Fluorine (F), Silicon (Si), Calcium (Ca), Sodium (Na), Cobalt (Co)
Fluorine (F)
. It is a very hot day. The weather forecast calls for a cold front to suddenly move through the area. What are you most likely to see first?
Fog or clouds
Both gases and liquids:
Have an indenite shape.
What is the purpose of processing a substance with a mortar and pestle?
Increase the surface area of a substance.
Which element is found in the group described by the statement below? This group contains poisonous, very reactive elements often used in bacteria killing or household cleaners. Xenon (Xe), Iodine (I), Helium (He), Sodium (Na), Hydrogen (H)
Iodine (I)
As you move from left to right on the periodic table, what generally happens to the metallic character of elements?
It decreases.
As you move from left to right on the periodic table, what generally happens to the boiling point of elements?
It increases, then decreases.
. As you move from top to bottom on the periodic table, what generally happens to the metallic character of elements?
It increases.
As you move from left to right on the periodic table, what happens to the electronegativity?
It increases.
As you move from top to bottom on the periodic table, what happens to the atomic radius?
It increases.
Which of the following can be found in the second period of the periodic table? Uranium (U), Lithium (Li), Magnesium (Mg), Potassium (K), Helium (He)
Lithium (Li)
Magnesium has three common isotopes. Based on its average atomic mass, which is the most common?
Magnesium-24
Which quantum number indicates the position of the orbital?
Magnetic
Which of the following is a physical change?
Melting ice.
Which scientist used the oil drop experiment to measure the charge of individual electrons?
Millikan
Which of these elements has the smallest atomic radius? Bismuth (Bi), Phosphorus (P), Nitrogen (N), Arsenic (As), Antimony (Sb)
Nitrogen (N)
If Atom #1 has 19 protons and 22 neutrons, and Atom #2 has 20 protons and 22 neutrons, are these isotopes of the same element?
No, because they have different numbers of protons.
Based on Avogadro's number, which of the following is NOT true? (For reference: the molecular mass of hydrogen is 1 g/mol, the molecular mass of oxygen is 16 g/mol.)
One mole of hydrogen atoms has a mass of 2 grams.
_____ properties of matter can be determined without changing composition, while _____ properties of matter must change the composition of matter.
Physical; chemical
Which of the following will react violently with water to form a base? Chlorine (Cl), Potassium (K), Calcium (Ca), Cobalt (Co), Aluminum (Al)
Potassium (K)
How does the Bohr Model differ from the Rutherford model?
Rutherford assumed that the position of electrons was random, while Bohr identified that they were located in very specific energy levels.
Which of these elements has the largest atomic radius: argon, phosphorus, aluminum, sodium or magnesium?
Sodium (Na)
Which family has the lowest electronegativity?
The alkali metals
What does it mean that matter is conserved in physical and chemical changes?
The amount of matter stays the same.
An air conditioner and a refrigerator use a gas that easily converts to a liquid and back again. What part of both machines accomplish this?
The condenser
What did Rutherford discover in his gold foil experiment?
The nucleus is positively charged, small, and dense.
Why are metals good conductors of electricity?
Their outer electrons are held very loosely
X and Y are elements that are isotopes to each other. Which of the following is true about X and Y?
They have different numbers of neutrons.
How are isotopes of the same element similar?
They have the same number of protons.
Which of the following causes water beads on the outside of a cold glass of water?
Water vapor in the atmosphere condensing onto the glass.
Which of the following is an example of when an electron absorbs energy?
When it goes from the second energy level to the fourth.
The ability of iron to react to oxygen is an example of _____
a chemical property.
The average atomic mass or atomic weight found on the periodic table is _____.
a weighted average based on the abundances of all naturally occurring isotopes of an element
Elements in Group 2 are known as the _____.
alkaline earth metals
Electronegativity is the ability of an atom to _____
attract electrons.
Which elements listed is likely to be the most reactive? beryllium, magnesium, calcium, strontium, barium
barium
Which of the following elements has the same number of valence electrons as aluminum? zinc, carbon, magnesium silicon, boron
boron
Which letter orbital corresponds to l = 2?
d
Which block is manganese (Mn) located in?
d-block
Which of the elements below has the highest ionization energy? carbon (C), barium (Ba), fluorine (F), calcium (Ca)
fluorine (F)
Which of the elements below has the smallest ionization energy? francium (Fr), sodium (Na), aluminum (Al), bromine (Br)
francium (Fr)
When writing electron configurations, electrons are represented in their lowest possible energy state, called their _____.
ground state
When heating a solution, a _____ is the best option for highly flammable substances.
hot plate
Which of the following is NOT an example of a compound?
hydrogen
The nucleus of an atom:
is positively charged.
As you move from top to bottom on the periodic table, what generally happens to the ionization energy?
it decreases
As you move from left to right on the periodic table, what generally happens to the ionization energy?
it increases
Which of the following are arranged from smallest unit to largest unit?
mm, cm, m, km
Which of the following sets of quantum numbers CAN exist?
n = 2, l = 0, ml = 0, s = +1/2
What is the largest principal quantum number that a calcium electron can have?
n = 4
What should the electron configuration for neon (Ne) end with? Is it going to be a stable atom or a reactive atom?
p^6, stable
When an electron moves from an excited state to a ground state, it will _____.
release energy
What is ionization?
removing electrons from an atom
Homogeneous mixtures are also called
solutions
ALL atoms of the same element have:
the same number of protons.
The mass number indicates:
the total number of protons and neutrons.