Questão 1
Questão
A 9.0 g sample of solid sodium bicarbonate completely decomposes into solid sodium hydroxide and carbon dioxide gas when heated. After the sodium hydroxide cools it has a mass of 4.74 g. According to the Law of Conservation of Mass, what mass of carbon dioxide must have been formed?
Responda
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a) 4.67 g
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b) 4.26 g
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c) 4.3 g
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d) 13.7 g
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e) none of the above
Questão 2
Questão
A substance that can only be separated by chemical means is:
Questão 3
Questão
Which of the following statement(s) is(are) not correct?
Responda
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a) The conversion of compounds into elements is a chemical change.
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b) The conversion of sugar into carbon and water is a chemical change.
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c) The conversion of liquid water into gaseous water is a chemical change.
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d) The conversion of elements into compounds is a chemical change.
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e) The evaporation of water is a physical change.
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f) d and e
Questão 4
Questão
Which of the following is a mixture?
Questão 5
Questão
If the distance between layers of silicon atoms in graphite is given as 823 pm, what is the distance in cm?
Responda
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8.23 x 10^-10
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8.23 x 10^-12
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8.23 x 10^-7
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8.23 x 10^-8
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8.23 x 10^-6
Questão 6
Questão
A 0.75 kg sample of methylene chloride has a density of 1.32 x 10^3 mg/cm^3. What is the volume in L of methylene chloride?
Responda
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0.99 L
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5.7 L
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5.68 x 10^-1 L
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5.7 x 10^-1
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0.5682 L
Questão 7
Questão
The British physicist who won the Nobel Peace prize in 1906 for the discovery of the electron was:
Responda
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Ernest Rutherford
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JJ Thomson
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Robert Millikan
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James Chadwick
Questão 8
Questão
Which statement is not true of the nucleus of an atom?
Responda
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a) it contains the neutrons, protons and electrons
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b) it is at the center of an atom
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c) its overall charge is positive
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d) it contains most of the mass of an atom
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e) both a and d
Questão 9
Questão
The number of protons in a neutral atom of a given element is equal to:
Questão 10
Questão
How many protons, neutrons and electrons are in the isotope of Ni+2 having a mass number of 57?
Responda
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28p, 29n, 30e-
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57p, 29n, 28e-
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28p, 29n, 26e-
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28p, 57n, 26e-
Questão 11
Questão
The formulas of the phosphate ion, the ammonium ion and the perchlorate ion are represented by:
Responda
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PO4-3, NH4+, ClO3-
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PO3-2, NH3+, ClO2-
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PO4-3, NH4+, ClO4-
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PO4-2, NH4+, ClO4-
Questão 12
Questão
The formula for potassium sulfide is:
Questão 13
Questão
How many atoms of Ca are there in 2.11 g of Ca?
Responda
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3.11 x 10^+22
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8.75 x 10^-26
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1.27 x 10^+24
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3.11 x 10^+23
Questão 14
Questão
Which of the following statements is true for acetic acid, C2H4O2?
Responda
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2 mole C2H4O2 contains 2 moles C
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3 mole C2H4O2 contains 8 moles H
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5 mole C2H4O2 contains 10 moles O
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1 mole C2H4O2 contains 1 moles C
Questão 15
Questão
How many grams of oxygen are there in 25 g of Al2O3?
Responda
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1.17 x 10^1 g
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12 g
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3.9 g
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1.2 x 10^25 g
Questão 16
Questão
What is the mass percentage of Cl in 1 mole C14H9Cl5?
Responda
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50.02%
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47.42%
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10.01%
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75.09%
Questão 17
Questão
What is the percent yield of Cu in an experiment if the actual yield is 12.01 g and the theoretical yield is 14.15 g?
Responda
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117.8%
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84.87%
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2.14%
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71.09%
Questão 18
Questão
A soluble molecular compound has the ability to conduct electricity.
Questão 19
Questão
Which of the following is(are) example(s) of a weak electrolyte?
Responda
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a) HCl
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b) NH3
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c) KOH
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d) HCN
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e) b and c
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f) b and d
Questão 20
Questão
When AgNO3 reacts with HCl the products are:
Responda
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a) H2 (g)
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b) nitric acid
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c) AgCl (s)
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d) AgCl (aq)
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e) b and c
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f) b and d
Questão 21
Questão
What is the net ionic equation when HC2H3O2 reacts with NaOH?
Responda
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HC2H3O2(aq) + NaOH(aq) -> C2H3O2Na(aq) + H2O(l)
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H+(aq) + OH-(aq) -> H2O(l)
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HC2H3O2(aq) + 2OH-(aq) -> C2H3O2-(aq) + 2 H2O(l)
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HC2H3O2(aq) + OH-(aq) -> C2H3O2-(aq) + H2O(l)
Questão 22
Questão
A Bronsted-Lowry acid/base reaction is best defined as:
Questão 23
Questão
A diprotic acid has ___ acidic protons.
Questão 24
Questão
The gas formed when Na2S reacts with H2SO4 is:
Questão 25
Questão
What are the oxidation sates of each element in KClO2?
Responda
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K=+1, Cl=+5, O=-2
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K=-1, Cl=+5, O=-2
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K=+1, Cl=-5, O=-2
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K=+1, Cl=+5, O=+2
Questão 26
Questão
CuCl2(aq) + Mg(s) -> MgCl2(aq) + Cu(s) is an example of a:
Responda
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a) combination reaction
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b) combustion reaction
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c) displacement reaction
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d) redox reaction
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e) b and d
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f) c and d
Questão 27
Questão
The kinetic energy of a 151 lb person with a velocity of 2.0 m/s is: (given 1lb=0.4536kg)
Responda
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a) 1.4 x 10^2 J
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b) 1.4 x 10^-2 kgm^2/s^2
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c) 1.4 x 10^-2 J
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d) 1.4 x 10^2 kgm^2/s^2
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e) a and d
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f) b and c
Questão 28
Questão
Calculate the quantity of heat required (q) to raise the temperature of a 0.103 g sample of Cu by 10.0°C given a specific heat of 0.384 J/g°C.
Responda
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0.0396 J
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03.84 J
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0.3955 J
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0.396 x 10^3 kJ
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0.396 J
Questão 29
Questão
Internal energy, U is best defined as:
Responda
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the sum of the kinetic and potential energies of all particles making up a substance
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the total sum of all energies contained within a system
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positional energy
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the energy contained within the nucleus of an atom
Questão 30
Questão
What is true of the relationship between the energy, the frequency and the wavelength of light:
Responda
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as energy increases, frequency decreases and wavelength decreases
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as energy decreases, frequency decreases and wavelength decreases
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as energy increases, frequency increases and wavelength decreases
Questão 31
Questão
When an electron transitions from the n=1 to the n=4 energy level light is emitted.
Questão 32
Questão
Which transition below best describes the absorption of the longest possible wavelength of light?
Responda
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n=1 to n=6
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n=2 to n=1
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n=7 to n=8
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n=8 to n=7
Questão 33
Questão
The value of the principal quantum number is referring to:
Questão 34
Questão
An electron having n=3 and a l=2 must be in the:
Responda
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3p subshell
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3d subshell
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3s subshell
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3f subshell
Questão 35
Questão
A 2p subshell contains how many orbitals?
Questão 36
Questão
When l=4, n must have a minimum value of :
Questão 37
Questão
According to the energy order building up principle which statement(s) below is never correct.
Responda
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a) 3p fills after 3s
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b) 4s fills before 3d
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c) 2s fills after 1s
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d) 5s fills before 4p
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e) a and d
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f) b and d
Questão 38
Questão
Choose the correct statement below in terms of atomic size.
Responda
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Te<Ag<Ru<Rb<Cs
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Ru<Ag<Te<Rb<Cs
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Cs<Ag<Te<Rb<Cs
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Cs<Rb<Ru<Ag<Te
Questão 39
Questão
Ionization energy refers to the amount of energy required to add an electron to the valence shell of a gasoline atom.
Questão 40
Questão
Which species would you expect to have the greatest ionization energy associated with it?
Questão 41
Questão
How many electrons are shared when the ionic compound MgS2 is formed?
Questão 42
Questão
Which of the following is correct in terms of ionic radii:
Responda
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Te-2<At-1<Cl-<S-2<P-3
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S-2<Cl-<At-1<P-3<Te-2
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Cl-<S-2<P-3<Te-2<At-1
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P-3<Te-2<At-1<Cl-<S-2
Questão 43
Questão
Which of the following would you expect to have the highest melting point?
Questão 44
Questão
Which noble gas is Ca+2 isoelectronic with?
Questão 45
Questão
Which is the most electronegative atom?
Questão 46
Questão
Which atoms are most likely to form triple bonds?
Responda
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C, N, O and Cl
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C and P
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C and O
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C, N and S
Questão 47
Questão
Which bond is most polar?
Questão 48
Questão
How many resonance Lewis electron dot structures does O3 have?
Questão 49
Questão
Which bond would require the most energy to break?
Questão 50
Questão
The molecule CO2 is a polar molecule.
Questão 51
Questão
Which of the following describes the bond angles if a central atom has 5 groups around it?
Responda
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90° and 180°
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90°, 120° and 180°
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120°
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90°
Questão 52
Questão
What is the name of the molecular geometry about the central atom in PCl3?
Responda
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trigonal pyramidal
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tetrahedral
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bent
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distorted tetrahedron
Questão 53
Questão
Which of the following is a nonpolar molecule?
Questão 54
Questão
What is the hybridization about the Xe atom in XeF4?
Questão 55
Questão
Which statement below is most accurate with regard to the total number of σ and π bonds in HCOCH3?
Responda
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5 σ and 2 π bonds
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7 σ bonds
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6 σ and 1 π bonds
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1 π bond