Chemistry
Chemical reactions, stoichiometry, molecular structures, and element properties.
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select the correct answer. why does common table salt (nacl) have a hig…
A. It forms an ionic bond with a crystal lattice structure.
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select the correct answer. methane (ch₄) burns in oxygen to produce car…
B. combustion
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select the correct answer. using this activity chart, which reaction wi…
B. No reaction occurs.
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select the correct answer. when an atom in a reactant gains electrons, …
A. Its oxidation number decreases.
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select the correct answer. give the name and formula of the compound fo…
A. manganese phosphate: $Mn_{3}(PO_{4})_{2}$
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identifying technologys effect how has technology affected the curiosit…
All of the above (assuming all the listed statements are true in the context of the mission's technological - enabled achievements).
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which model can be described as negatively - charged electrons orbiting…
The Bohr Model
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heisenberg proposed the idea that if an electron moves as a wave, it wo…
The Uncertainty Principle
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which of the following best describes an electron cloud? a collection o…
Electron - containing regions that exist around the nucleus
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the modern atomic theory shows us that electrons do not travel in defin…
There are regions that exist within an atom where electrons are likely to exist.
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near the end of the 18th century the first atomic theory was developed.…
Electrons orbit the nucleus in electron clouds
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complete this quiz to finish the assignment for chemistry - p8 due on s…
Physical; chemical
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which of the following is not an example of a compound? water limestone…
C. hydrogen
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in order to find out the empirical formula of a compound such as copper…
La formule empirique est $Cu_{2}O$.
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instructions: choose an answer and hit next. you will receive your scor…
the mixture of water and salt can be physically separated.
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instructions: choose an answer and hit next. you will receive your scor…
A compound.
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a mass spectrometer measures neon to have two masses: 20 and 22 atomic …
A. isotopes
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which of the following contains the most moles of atoms? answer: a 1 g …
A. 1 g of helium
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a pharmacist has 80 milliliters of a 25% saline solution. which express…
$y=\frac{0.25(80)+0.1x}{80 + x}\times100$ (corresponding to the fourth option in the original multiple - choice list)
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which of the following represents a species with 39 protons and 36 elec…
D. $Y^{3+}$
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determine the molar mass of c₆h₁₂o₆. provide an answer to two decimal p…
180.18 g/mol
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there are two naturally occurring isotopes of europium, $^{151}\text{eu…
C. 50%
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how many protons are in an atom of strontium - 90? answer: a 2 b 38 c 8…
B. 38
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how many protons (p) and electrons (e) are found in a se²⁻ ion? answer:…
A. 34 p, 36 e
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the net charge on an atom of a given element changes as ____ are added …
C. electrons
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the net charge on an atom of a given element changes as ____ are added …
D. protons and electrons
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which particle(s) may be found in the nucleus of an atom? answer: a pro…
B. proton and neutron
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neutral atoms of all isotopes of a given element have the same ______. …
C. number of electrons
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how many molecules are in 47.3 moles of co₂? answer: molecules
$2.848406\times 10^{25}$
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what is the mass in grams of 34.9 moles of nacl?
2039.556
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determine the quantity in moles of rbf that are in 89.6 grams of rbf.
$0.858$
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calculate the number of atoms of o in 7.23 moles of fe(no₃)₃.
$3.93\times 10^{25}$ atoms
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how many neutrons are in a ⁴he atom? answer: a 0 b 2 c 4 d 6
B. 2
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how many h atoms are in one formula unit of (nh₄)₂so₄?
8
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which of the following is an example of an empirical formula? incorrect…
C. $C_7H_{14}Cl_2$
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which of the following is an example of an empirical formula? a c₂h₂o₂ …
D. $C_{6}H_{9}O_{3}$
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what is the mass number of zinc - 68?
68
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which of the following species has the same number of electrons as cl⁻?…
A. S²⁻
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what element with a mass number of 100 has 56 neutrons in its nucleus? …
B. ruthenium (Ru)
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determine the number of moles in 1.49e23 formula units of cacl₂.
$0.247$
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how many neutrons are in an atom of uranium - 235? answer: a 92 b 143 c…
B. 143
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which of the following pairs represent isotopes? a: (^{28}\text{si}) an…
C. \(^{28}Si\) and \(^{29}Si\)
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when methane is completely combusted in oxygen forming carbon dioxide a…
C. The masses of the reactants and products are equal.
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what is the mass number for an atom of xenon containing 54 protons and …
131
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terephthalic acid is a chemical used to make polyesters, including disp…
D. $C_8H_6O_4$
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what is the atomic symbol and mass number for an atom containing 50 pro…
B. $^{114}\text{Sn}$
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an unknown element x has the following isotopes: ²⁵x (80.50% abundant, …
$25.41$ amu
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how many electrons are in a neutral $^{41}$ca atom? answer: a 2 b 20 c …
B. 20
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determine the molar mass of ag3n. provide an answer to two decimal plac…
337.62 g/mol
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identify the missing product in the following acid - base reaction. • i…
$Li_{2}CO_{3}$
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question predict the products of the following acid - base reaction. • …
$H_2O$; $NaCl$
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question identify the missing product in the following acid - base reac…
$FeF_{2}$
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balance the following acid - base reaction. • use the simplest possible…
$H_2SO_4 + 2LiOH \longrightarrow 2H_2O+1Li_2SO_4$
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fill in the blank coefficients in order to balance the following chemic…
1, 1, 1
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question fill in the blank coefficient in order to balance the followin…
3
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using the chemical equation provided, identify which of the following a…
- A. Fe - B. O₂
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using the chemical equation provided, identify which of the following a…
B. 4, C. 3
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identify the balanced chemical equation. select the correct answer belo…
D. 2 Fe + 3 Cl₂ → 2 FeCl₃
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question substances that are only present when a chemical reaction is c…
B. products
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fill in the blank coefficient in order to balance the following chemica…
2, 2
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the substances generated by the chemical reaction are known as: select …
A. products
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question 4 what are the negative consequences of organic farming? leach…
D. All of the above
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6. how many atoms of mercury are in 65.0 grams of it?
$1.95\times 10^{23}$ atoms
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what is the mass in grams of 3.7 moles ch₄? select the correct answer b…
B. 59 g
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how many grams of oxygen are there in 2.5 moles of oxygen (o₂) molecule…
C. 80. g
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5. how many moles are in 9.50 x 10^{25} atoms of copper?
$158$ mol
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the mass of 1 mole of co₂ is: select the correct answer below: 44 moles…
D. 44 grams
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4. how many grams are in 4.77 mol of iron?
266.30 g (rounded to two decimal places)
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compare 1 mole of hydrogen with 1 mole of oxygen. they will have: selec…
The same number of atoms and different masses.
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how many moles of pcl₅ are present in a 100.0 g sample? select the corr…
C. 0.48
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for each list, place elements in order of least to greatest electronega…
1) Na, Si, Cl 2) In, Ga, B 3) Na, Si, O
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3. how many grams of bromine are there in 1.00 x 10^9 bromine atoms?
$1.32\times 10^{-13}$ g
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type the element in each list with the largest electronegativity: k, fr…
Li Cl F N
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2. how many atoms are in 6.85 mol of neon?
$4.13\times 10^{24}$ atoms
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a ______ is defined as the amount of substance containing the same numb…
B. mole
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for each list, place elements in order of least to greatest ionization …
1) Li, O, N 2) Ra, Ba, Si 3) Pb, Sn, C
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1. how many moles are in 9.20 g of nitrogen?
0.657 mol
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type the element in each list with the largest ionization energy: te, p…
Se Te F Cl
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abbreviated atomic notation # of protons # of neutrons # of electrons f…
| Abbreviated Atomic Notation | # of Protons | # of Neutrons | # of Electrons | |---|---|---|---| | F - 37 | 9 | 28 | 9 | | | 38 | 48 | 38 | | Co - 55 | 27 | 28 | 27 |
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complete atomic notation, # of protons, # of neutrons, # of electrons 3…
| Complete Atomic Notation | # of Protons | # of Neutrons | # of Electrons | |---|---|---|---| | $_{34}^{65}Se^{2 -}$ | 34 | 31 | 36 | | $_{13}^{28}Al^{3+}$ | 13 | 15 | 10 | | $_{…
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type the element in each list with the largest atomic radius: na, al, m…
Na Rb Ba Fr
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for each list, place elements in order of least to greatest atomic mass…
1) N, As, Bi 2) Ne, Ar, Rn 3) Ca, Fe, Pb
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type the element in each list with the largest atomic mass: n, li, be b…
N At Te Cl
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atomic mass the atomic mass of elements increases moving ? each group a…
DOWN, RIGHT
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identify the number of valence electrons found in each element. al c ne…
Al: 3 C: 4 Ne: 8 K: 1 S: 6 Br: 7 P: 5 Ca: 2
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what are valence electrons? • electrons found in the outermost energy l…
First atom: Element Name: Oxygen, Valence Electrons: 6 Second atom: Element Name: Beryllium, Valence Electrons: 2
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type the symbol of each element that is described below: the lightest t…
The lightest Transition Metal: Sc The heaviest Alkali Metal: Fr The third Halogen element: Br The fourth Noble Gas element: Kr
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identify the correct elements being described below: the alkaline earth…
1. Ra 2. Cu 3. He
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identify the correct elements being described below: the only group 1 e…
1. H. Hydrogen 2. Li. Lithium 3. Cl. Chlorine
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sort the items in the answer key into the correct category below: drag …
Group 1: Alkali Metals Group 2: Alkaline Earth Metals Groups 3 - 12: Transition Metals Group 17: Halogens Group 18: Noble Gases Below the main groups: Lanthanides and Actinides
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part 3 (1 point) which of the following statements is true about the tw…
Both HCN and HNC have +1 and -1 formal charges, but in HCN the negative formal charge is on the more electronegative atom.
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sort the groups into their correct location on the periodic table: answ…
From left - to - right (based on the arrows in the image): 1. Alkali Metals 2. Alkaline Earth Metals 3. Transition Metals 4. Halogens 5. Noble Gases
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classify each element below as a metal, nonmetal, or metalloid. na br a…
Na: Metal Br: Nonmetal Au: Metal Si: Metalloid N: Nonmetal Ge: Metalloid
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types of elements the periodic table contains three types of elements: …
Top '?': Nonmetals Middle '?': Metals Bottom '?': Nonmetals
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type the group and period where each element is found: cl chlorine → gr…
Cl: Group 17, Period 3 Ba: Group 2, Period 6 Ag: Group 11, Period 5
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type the symbol of the element found at each location below: group 16, …
Group 16, Period 5: Te Group 2, Period 4: Ca Group 17, Period 2: F Group 8, Period 4: Fe
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14. how many moles of nickel(iv) sulfate: ni(so₄)₂ is 120.5 g of nickel…
$0.48\ mol$ ### 15.
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2 the total energy an object possesses because of the random motion of …
Thermal energy
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31 a chemical reaction where thermal energy (heat) is released is what …
D. Exothermic reaction
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22 carbonic acid is a strong acid that causes weathering to rocks such …
B. False