Physical Science unit 3: speedback quizzes, quizzes, and vocab
What is the charge of iron (Fe) in the compound Fe2O3?
+3
A metal is..
A network solid consisting of positively charged atoms in a sea of electrons
Which of the following would best describe the characteristics of the material formed? with carbon and oxygen
A non-conducting material with low melting and boiling points, likely liquid or gas at room temperature
If GaAs forms a semiconductor like Ge, which of the following elements will form a semiconductor like Si?
Al and P
Compounds between two different metals are called
Alloys
When you compare saturated with unsaturated fatty acids containing the same number of carbon atoms, what is true?
Saturated fatty acids have more hydrogen atoms.
Fill in the blanks and tell what type of radioactive process the equation represents, fission, fusion, alpha decay, beta decay, gamma decay. 1. 23592U + 10n → 14054Xe + ___ + 310n
Sr-93, fission
Two or more different elements that are chemically combined are always
a compound.
Nuclear fission is when
a large nucleus breaks apart into smaller pieces
In which of the following processes is the end product more ordered than the reactants? (In which process does entropy decreases.) Select one: a. 2H2 (gas) + O2 (gas) = 2 H2O (gas) b. 2C8H18 (liquid) + 25O2 (gas) = 16CO2 (gas) + 18H2O(gas) c. C6H12O6 (solid) + 6O2 (gas) = 6CO2 (gas) + 6H2O (liquid) d. 2C7H5N3O6 (solid) = 3N2(gas) + 7CO(gas) + 5H2O(gas) + 7 C(solid) e. NaHCO3(solid) + C2H4O2(liquid)=C2H3NaO2(solid)+ H2O(liquid) + CO2 (gas)
a. 2H2 (gas) + O2 (gas) = 2 H2O (gas)
Which of the following is NOT used as a technique for identifying chemical substances? Select one: a. Mettler spectroscopy b. Crystallography c. Electronic spectroscopy d. Mass spectroscopy e. Vibrational spectroscopy
a. Mettler spectroscopy
Which of the following is atomic matter rather than molecular or network matter? a. Neon gas b. water c. magnesium chloride d. silver e. white gold
a. Neon gas
Why are alloys useful to us today?
a. have lower melting temperatures. c. are less malleable. d. reduce weight in objects.
What is the approximate range of the nuclear strong force? (In other words, what is the distance over which the strong force is significant?)
about the size of a nucleus
An unstable nucleus which has a tendency to spontaneously change its form with the emission of high-energy particles or photons is said to be
radioactive
Which is the best definition of an alloy?
solid mixture of metals
. How many double bonds exist between carbon atoms in these saturated fatty acids?
zero
Current can flow in all directions in an LED?
false
Dispersion forces are stronger than covalent bonds.
false
Fatty substances that are solid at room temperature are classified as oils.
false
Metals have higher ionization energies than non-metals do.
false
Mica is a silicate that has strong bonds throughout its entire structure.
false
Molecular orbitals are the same shape as atomic orbitals.
false
The energies of the orbitals that form when metals interact are very widely spaced in energy.
false
The forces between the N2 molecules in a container of N2 are very strong.
false
Which of the following set of properties is most likely those associated with methane, a covalently bonded compound?
gas at room temperature, colorless, does not conduct electricity when solid
Isotopes of an element are different atoms of the element that...
have the same number of protons, but differ in mass number.
How would you describe the melting point of a substance formed by a substance containing molecular ions?
high
Which of the following tends to have the highest melting and boiling points?
network matter
is it possible to predict exactly when a radioactive nucleus will decay?
no
onic compounds are formed between a metal and a
non- metal
Fill in the blanks and tell what type of radioactive process the equation represents, fission, fusion, alpha decay, beta decay, gamma decay. 4. 2210Ne → ___ + 00photon
Ne-22, gamma
When are molecular conductors of electricity?
When they combine with metals and are then melted or dissolved
The process that produces most of the explosive energy of a hydrogen bomb, and that is believed to be responsible for the energy released by the sun, is called
nuclear fusion
Each molecule of nitric acid has the formula HNO3. If there are 6000 oxygen atoms present and 6000 nitrogen atoms present, how many hydrogen atoms will be required to convert all of the oxygen atoms into nitric acid?
2000
Uranium-238 alpha decays, emitting a helium-4 nucleus. What is the mass number of the product?
234
Which of the following would best describe the room temperature characteristics of ionic substance?
. Brittle, transparent, electrically non-conducting solid.
Locate the elements palladium (Pd, atomic #46) and nickel (Ni, atomic #28) on the periodic table. If Pd is combined with Ni, which of the following characteristics will the product show at room temperature?
. Shiny, malleable solid.
Carbon-14 ( 14C) is not stable and it spontaneously decays into nitrogen-14 ( 14N) and an electron by a radioactive beta-decay. Which of the following is true about the decay?
. The total number of nucleons stays the same.
How many protons does tritium, 3H, have?
1
true or false. electrons or ions are free to move in solid state in.. 1. covalent 2. ionic 3. metallic
1. false 2. false 3. true
true or false. bonds are long range 1. covalent 2. ionic 3. metallic
1. false 2. true 3. true
true or false. bonds are localized 1. covalent 2. ionic 3. metallic
1. true 2. false 3. false
true or false. bonds arise from electrostatic interactions in.. 1. covalent 2. ionic 3. metallic
1. true 2. true 3. true
true or false. energy levels are widely spaced in.. 1. covalent 2. ionic 3. metallic
1. true 2. true 3. false
2. A sample of radioactive material with a half-life of 6 hours sits for a day (24 hours). How much of the original radioactive material remains? ____
1/16 of the original amount
1. A sample of radioactive gas is produced. After 20 minutes, only 1/4 of the original gas remains. What is the half-life of the gas? ______
10 minutes
In the chemical equation C6H12O6 + 3O2 = 3CO2 + 6H2O, how many oxygen atoms are on the right side of the equation?
12
How many neutrons does tritium, 3H, have?
2
In Lesson 20, a magnesium strip was used to ignite the thermite reaction. When magnesium is placed in a flame from a small blow torch, it burns quite brightly forming magnesium oxide, a salt that contains one magnesium for every oxygen. In the following questions you will be asked to provide some details of the chemical processes involved in a reaction between magnesium and oxygen. How many more electrons does unbound oxygen need to fill its 2nd shell? (You may find it helpful to draw the energy well on scratch paper.)
2
In the equation C2H4 + 3O2 = ? CO2 + 2H2O, how many CO2 molecules are needed to balance the equation?
2
In Lesson 20, a magnesium strip was used to ignite the thermite reaction. When magnesium is placed in a flame from a small blow torch, it burns quite brightly forming magnesium oxide, a salt that contains one magnesium for every oxygen. In the following questions you will be asked to provide some details of the chemical processes involved in a reaction between magnesium and oxygen. Which of the following would best describe the room temperature characteristics of the substance that results from the reaction?
Brittle, transparent, electrically non-conducting solid.
What happens to the entropy of the universe as the products are formed?
Chemical potential energy is converted into thermal energy resulting in an increase in entropy.
In order for a chemical reaction to occur:
Entropy must increase as a result of the reaction
Which of the following fatty acids is best for human health?
Fatty acids that have one or more 'bent' cis-double bonds between carbon atoms.
Fill in the blanks and tell what type of radioactive process the equation represents, fission, fusion, alpha decay, beta decay, gamma decay. 3. 24195Am → 23793Np + ____
He-4, alpha decay
Fill in the blanks and tell what type of radioactive process the equation represents, fission, fusion, alpha decay, beta decay, gamma decay. 2. ___ → 19379Au + 0+1e + 00neutrino
Hg-193, beta decay
Why is a high temperature required for nuclear fusion to occur?
High temperatures are required to allow the nuclei to have enough kinetic energy to overcome the electromagnetic repulsion and have the strong force attraction take place
In a bonding orbital between two atoms, where is the electron density the highest? (Where do you have the highest probability of detecting an electron?)
In between the two atoms.
If a certain LED (doped semi-conductor) is cooled in liquid nitrogen, the color moves to a higher frequency. What happens to the band gap?
It increases in energy.
How does a catalyst affect a reaction?
It lowers the activation energy
Ammonium nitrate (NH4NO3), a common fertilizer, is an ionically bonded substance involving two polyatomic ions, ammonium (NH4+) and nitrate (NO3-). Ammonium nitrate dissolves well in a polar solvent such as water. Which of the following statements best describes what happens when this fertilizer dissolves in water?
The compound breaks up into the two oppositely charged ions. The ions do not break apart.
What happens to the energy of the Mg and Cl as this compound is formed?
The energy decreases.
What is the best description of activation energy?
The energy that must be put into a system before a reaction can take place.
What happens to the valence electrons as the product (MgO) is formed?
The magnesium atoms' valence electrons are effectively transferred to oxygen
What happens to the valence electrons as an ionic compound is formed?
The metal atoms' valence electrons are effectively transferred to non-metal.
Both fission and fusion can result in a release of energy. Why?
The nuclei of atoms near the middle of the periodic table have the least energy and the nucleons with the smallest mass.
The oxidation state of an atom refers to
The number of electrons gained or lost when an ionic bond is formed
When you compare the mass of the products to the mass of the reactants in a fission reaction, what do you find? (note the question is asking about mass, not mass number)
The reactants have more mass
Why do natural unsaturated fats have a lower solidification temperature than saturated fats?
They have curved hydrocarbon tails keeping individual molecules farther apart.
What best describes how the oxygen molecules would behave if mixed with water?
They would dissolve poorly or not at all because they are not polar.
Fish that swim in the cold north Atlantic would have what type of fatty acid in their blood?
Unsaturated acids with lots of double bonds.
When do polyatomic ions form crystals?
When they combine with metal atoms to form salts. and When they combine with other non-metal atoms.
Which of the following is a correct comparison of metals and semi-conductors? Select one: a. Metals have a larger band gap than semi-conductors. b. Metals' resistance increases when temperature increases while a semi-conductors resistance decreases. c. Semi-conductors' molecular orbitals overlap while metals' don't. d. Metals have more valence electrons than semi-conductors. e. Metals have larger electrical resistance than semi-conductors.
b. Metals' resistance increases when temperature increases while a semi-conductors resistance decreases.
What would make a legitimate radioactive decay?
both charge and mass number are conserved
Which of the following is an ionic compound? Select one: a. O2 b. NH3 c. MgF2 d. CO2
c. MgF2
Which of the following pairs would you expect to be covalently bonded? Select one: a. Co and Al b. P and Ca c. S and Br d. Ar and Cl
c. S and Br
The substance most likely to be a pure element is
copper.
What type of bond would exist between the carbon and the oxygen?
covalent
if you see the word molecule, what type of bond is present
covalent
Which of the following is NOT a characteristic of a metal or alloy? Select one: a. Electrically Conductive b. Thermally Conductive c. Malleable d. Brittle
d. brittle
Rank the following according to their strength, weakest first, strongest last. dipole-dipole interactions dispersion forces covalent bonding hydrogen bonding
dispersion forces, dipole-dipole interactions, hydrogen bonding, covalent bonding
Fill in the blanks and tell what type of radioactive process the equation represents, fission, fusion, alpha decay, beta decay, gamma decay.
electron, beta
What happens to the overall entropy in the universe as this compound is formed?
entropy increases
A very fast reaction has a very high activation energy.
false
What happens to the melting temperature as the size of the molecule increases?
increases
Which of the following is NOT important in the determining the characteristics of fatty acids? Select one: a. covalent bonds b. dispersion forces c. hydrogen bonds d. ionic bonds
ionic bonds
What will end of the graph be higher or lower than the beginning energy if the reaction absorbed energy?
it will be higher than the start
What happens to the missing mass in fusion?
mass is turned into energy so the resulting particles will be moving very fast (be very hot)
The process known as nuclear fission is primarily responsible for...
the energy produced by a nuclear reactor
The purpose of the control rods in a nuclear fission reactor is
to absorb neutrons, thus limiting the number of nuclei undergoing fission
Energy and entropy are both involved in chemical reactions.
true
Hydrogen bonding between molecules increases melting and boiling points.
true
In minerals, the underlying atomic structure gives rise to large scale properties observable with the naked eye.
true
Metals do not let light through.
true
Metals have a greater tendency than non-metals do lose electrons.
true
N2 has a triple bond and is a gas at room temperature. True or False: The triple bond is a very strong bond.
true
Quartz is a silicate that has strong bonds throughout its entire structure.
true
Unsaturated fats are considered an essential part of a healthy diet.
true
The molecule will be more electronegative (negative)...
up and to the right