化学
化学反应、化学计量、分子结构与元素性质。
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question 4: an engineer designs a rigid steel tank that will be used fo…
E. The tank will open; 912 torr
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question 3: shown here are 2 connected flasks; the volume and the press…
A. 955 torr
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where does the smell of rain come from f... getting started play the vi…
Geosmin
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question 2: methane gas (ch₄), reacts with gaseous water to form carbon…
E. 750.
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getting started play the video to take the quiz. the video will automat…
Ozone
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13 multiple choice 6 points choose the correct chemical formula for the…
13. AuO 14. \(K_{3}N\) 15. \(SnO_{2}\)
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10 multiple choice 6 points name the following compound: k₃n potassium …
10. potassium nitride 11. \(CsI\) 12. \(AgCl\)
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7 multiple choice 6 points name the following compound: fei₂ iron iodin…
7. iron (II) iodide 8. cadmium oxide 9. gold (I) chloride
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multiple choice 6 points an ionic compound formula consists of: ○ a neg…
For the first question: a positively charged metal first, then a negatively charged non - metal. For the second question: lithium fluoride.
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3 multiple choice 6 points which of the following types of elements req…
Transition metals
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what are the effects of enzymes on chemical reactions? select all of th…
B. Enzymes decrease the activation energy. C. Enzymes increase the rate of the reaction.
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enzymes reactants products activation energy catalyst chemical reaction…
reactants, products, catalyst, activation energy, enzymes
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sulfur dioxide (so₂) is a gas released when volcanoes erupt. it can rea…
The third model.
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methanol (ch₃oh) can be used to prevent certain liquids from freezing i…
The third model (the one with one \(CO\) molecule and two \(H_{2}\) molecules as reactants) accurately represents the reaction \(CO + 2H_{2} ightarrow CH_{3}OH\).
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balance the following equation: ___ch₄ + ___o₂ → ___co₂ + ___h₂o when t…
1, 2, 1, 2
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hydrogen peroxide (h₂o₂) can be used to disinfect and clean surfaces ar…
The first model (the top - most model among the given options) is correct as it has the correct number of \(H\) and \(O\) atoms on both sides of the reaction (based on the balance…
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balance the following equation: ___c₃h₈+ ___o₂→___co₂+ ___h₂o when the …
1, 5, 3, 4
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an electric current can be used to decompose water (h₂o) into oxygen (o…
The second model (the one with two \(H_2O\) molecules on the left - hand side, one \(O_2\) molecule and two \(H_2\) molecules on the right - hand side) accurately represents the r…
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balance the following equation: ___c₂h₂+ ___o₂→___co₂+ ___h₂o when the …
\(2\), \(5\), \(4\), \(2\)
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balance the following equation: ___c₂h₄+ ___o₂→___co₂+ ___h₂o when the …
1, 3, 2, 2
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assess it! part 1 1. which is not true about all of these elements? a. …
C. They all have the same number of protons # 2.
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balance the following equation: ___fes + ___hcl→___fecl₂+ ___h₂s when t…
1, 2, 1, 1
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be produced by combining ethyne (c₂h₂) and hydrogen chloride (hcl). whi…
The second model (with one \(C_2H_2\) molecule and two \(HCl\) molecules as reactants) is correct. Because the chemical reaction \(C_2H_2 + 2HCl ightarrow C_2H_3Cl + C_2H_3Cl\) (v…
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balance the following equation: $\\ce{\\_\\_h_{2}so_{4} + \\_\\_bacl_{2…
1, 1, 1, 2
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chloromethane (ch₃cl) is used in the production of silicone adhesives. …
The second model accurately represents the reaction \(CH_{4}+Cl_{2} ightarrow CH_{3}Cl + HCl\) as it follows the correct stoichiometry (one - to - one ratio of reactants \(CH_{4}\…
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nitrous oxide (n₂o), also known as laughing gas, is used as an anesthet…
The third model.
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balance the following equation: __hcl + __naoh→__nacl + __h₂o when the …
1, 1, 1, 1
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chlorine dioxide (clo₂) is used in paper manufacturing to bleach wood p…
The first model (the top - most model among the given options) accurately represents the reaction.
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balance the following equation: __ag₂s + __cucl₂→__agcl + __cus when th…
1, 1, 2, 1
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balance the following equation: ___al + ___cucl₂ →___cu + ___alcl₃ when…
2, 3, 3, 2
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read the lines from act i, scene v of romeo and juliet. romeo to juliet…
C. Romeo’s lines make up one quatrain, which uses an abab rhyme scheme
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3. how can you determine if elements have the same chemical properties?
Elements that are in the same group (vertical column) of the periodic table have the same number of valence electrons and thus tend to have the same chemical properties.
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balance the following equation: ___al + ___fe₂o₃ →___al₂o₃+ ___fe when …
2, 1, 1, 2
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balance the following equation: ___li + ___hf→___lif + ___h₂ when the e…
2, 2, 2, 1
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balance the following equation: ___k + ___h₂o→___koh + ___h₂ when the e…
\(2\), \(2\), \(2\), \(1\)
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balance the following equation: ___ni(clo_{3})_{2} \\to ___nicl_{2} + _…
1, 1, 3
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2. how are periods and groups different from each other? write it! ques…
Periods are horizontal rows (same number of electron shells), groups are vertical columns (similar chemical properties due to same valence electrons).
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balance the following equation: __h₂co₃→__co₂ + __h₂o when the equation…
\(1\), \(1\), \(1\)
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balance the following equation: ___alcl₃→___al + ___cl₂ when the equati…
\(2\), \(2\), \(3\)
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balance the following equation: ___al₂o₃→___al + ___o₂ when the equatio…
2, 4, 3
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balance the following equation: __s₈+ __o₂ → __so₂ when the equation is…
1, 8, 8
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balance the following equation: ___h₂ + ___cl₂ → ___hcl when the equati…
\(1\), \(1\), \(2\)
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balance the following equation: ___ca + ___o₂→___cao when the equation …
2, 1, 2
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balance the following equation: __al + __o₂ → __al₂o₃ when the equation…
4, 3, 2
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hydrogen chloride (hcl) dissolved in water can be used to remove rust a…
| | Number of atoms in reactants | Number of atoms in products | |--|--|--| | \(H\) | \(2\) | \(2\) | | \(Cl\) | \(2\) | \(2\) |
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hydrogen peroxide (h₂o₂) can be used to lighten or bleach hair. it is p…
| | Number of atoms in reactants | Number of atoms in products | |--|--|--| | H | 2 | 2 | | O | 2 | 2 |
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ammonia (nh₃) is commonly used as a fertilizer for plants. it is made w…
| | Number of atoms in reactants | Number of atoms in products | |--|--|--| | H | 6 | 6 | | N | 2 | 2 |
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1. explain what a valence electron is.
A valence electron is an electron in the outermost shell of an atom, involved in chemical bonding and determining an atom's reactivity and bonding capacity.
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ammonium nitrate (nh₄no₃) is an important ingredient in many fertilizer…
\(NH_4NO_3(s)\to2H_2O(g)+N_2O(g)\)
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13. what does the arrow mean in the reaction below? h₂o₂ -> h₂o + o₂
The arrow means the direction of the reaction, showing that the reactant is being converted into products.
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acetic acid (hc₂h₃o₂) is the primary component of vinegar. it is produc…
\(\text{CH}_3\text{OH}_{(l)}+\text{CO}_2{(g)}+\text{H}_2{(g)}\longrightarrow\text{HC}_2\text{H}_3\text{O}_2{(l)}+\text{H}_2\text{O}_{(l)}\)
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determine the number of oxygen in 3ai(oh)3.
\( 9 \)
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acetic acid (hc₂h₃o₂) is the primary component of vinegar. it is produc…
\(CH_{3}OH(l)+CO_{2}(g)+H_{2}(g)\to HC_{2}H_{3}O_{2}(l)+H_{2}O(l)\)
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baking soda (nahco₃) is a common ingredient in muffins. it decomposes w…
\(2NaHCO_{3(s)}\to Na_{2}CO_{3(s)}+CO_{2(g)}+H_{2}O_{(g)}\) (the last option in the given choices)
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sulfuryl chloride (so₂cl₂) is a substance used to make chemicals for ki…
\(SO_2Cl_2(g)\to SO_2(g)+Cl_2(g)\) (the third option in the given choices)
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0.161 l of a 0.189 m solution is left on a hotplate overnight and the f…
\(1.41\times 10^{2}\space mL\)
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lithium nitride (li₃n) has the potential to be used as a solid electrol…
\(6Li(s)+N_2(g) ightarrow 2Li_3N(s)\) (the third option)
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a balloon is filled with 2.45 l helium at 1.01 atm. the balloon is then…
4.19
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hotdogs and hamburgers can be cooked on a propane grill. propane (c₃h₈)…
| | Number of atoms in reactants | Number of atoms in products | |---|---|---| | \(C\) | \(3\) | \(3\) | | \(H\) | \(8\) | \(8\) | | \(O\) | \(10\) | \(10\) |
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114.7 ml of 0.0371 m triprotic acid is neutralized using 24.1 ml of sod…
\(0.530\)
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carbon tetrabromide (cbr₄) is a component of some fire - resistant subs…
| | Number of atoms in reactants | Number of atoms in products | |---|---|---| | H | 4 | 4 | | Br | 8 | 8 |
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if a balloon is filled with air to a volume of 567. ml at a temperature…
$3.37\times 10^{2}$
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balance this equation- _secl₆+_o₂>_seo₂+_cl₂
\(1,2,1,2\)
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16/20 what is a coefficient? the small number on the right of the chemi…
The large number to the left of a formula.
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copper(ii) chloride (cucl₂) acts as a catalyst in the industrial produc…
| | Number of atoms in reactants | Number of atoms in products | |---|---|---| | \(Cu\) | 2 | 2 | | \(Cl\) | 4 | 4 | | \(Pd\) | 1 | 1 |
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balance this equation. _cf₄ + _br₂ → _cbr₄ + _f₂
1, 2, 1, 2 (i.e., \(1CF_4 + 2Br_2=1CBr_4 + 2F_2\))
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balance this equation- __p₄ + __o₂ --> __p₂o₃ 2, 1, 3 1, 3, 2 it is alr…
1, 3, 2
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match each description to the correct element. has the same number of e…
- Magnesium (Mg): has the same number of electron shells as Silicon, more reactive than Boron, has 2 valence electrons. - Carbon (C): has the same number of electron shells as Ber…
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balance this equation. _ch4 + _o2 --> _co2 + _h2o
1,2,1,2 (corresponding to the coefficients of \(CH_4\), \(O_2\), \(CO_2\), \(H_2O\) respectively)
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many common household lighters contain butane (c₄h₁₀). butane burns in …
| | Number of atoms in reactants | Number of atoms in products | |---|---|---| | C | 8 | 8 | | H | 20 | 20 | | O | 26 | 26 |
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balance this equation _zn+_hcl→_zncl₂+_h₂
\(1,2,1,1\) (corresponding to the coefficients for \(Zn\), \(HCl\), \(ZnCl_2\), \(H_2\) respectively, which is the option \(1,2,1,1\))
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balance this equation _n₂ + _h₂ --> _nh₃
1,3,2
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is this equation balanced?
no
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an electric current can be used to decompose water (h₂o) into oxygen (o…
| | Number of atoms in reactants | Number of atoms in products | |--|--|--| | \( H \) | \( 4 \) | \( 4 \) | | \( O \) | \( 2 \) | \( 2 \) |
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when balancing equations a ____ can be placed to the left of a formula …
B. coefficient
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benzene (c₆h₆) is used in the production of rubber. it is formed when e…
| | Number of atoms in reactants | Number of atoms in products | |--|--|--| | C | \(6\) | \(6\) | | H | \(6\) | \(6\) |
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balance this equation. _mg + _cl₂ --> _mgcl₂
A. already balanced
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balance this equation _ai +_hci → _h₂ +_aici3 4, 12, 3, 4 2, 1, 4, 5 2,…
2, 6, 3, 2
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at the end of chemical reactions, what is the total mass of the reactan…
the mass is the same
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methanol (ch₃oh) can be used to prevent certain liquids from freezing i…
| | Number of atoms in reactants | Number of atoms in products | |--|--|--| | \(C\) | \(1\) | \(1\) | | \(O\) | \(1\) | \(1\) | | \(H\) | \(4\) | \(4\) |
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zinc sulfide (zns) is used in glow - in - the - dark face paint. it is …
| | Number of atoms in reactants | Number of atoms in products | |--|--|--| | Zn | 1 | 1 | | Cl | 2 | 2 | | H | 2 | 2 | | S | 1 | 1 |
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balance this equation, _n₂+_o₂→_h₂o+_hno₃ not possible 2,2,1,4 2,1,1,4 …
not possible
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balance the chemical equation using the smallest possible whole number …
1, 4, 1, 4
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is the equation balanced?: 2h2o + o2 ---> 4mgo + 3fe
No
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balance the chemical equation using the smallest possible whole number …
1 \(CH_4(g)\) + 2 \(O_2(g)\) → 1 \(CO_2(g)\) + 2 \(H_2O(g)\)
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balance the chemical equation using the smallest possible whole number …
\(2Al + 3CuCl_2 ightarrow2AlCl_3+3Cu\)
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balance the chemical equation using the smallest possible whole number …
2, 1, 1, 1
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balance the chemical equation using the smallest possible whole number …
\(2\) \(C_{2}H_{4}(g)\to1\) \(C_{4}H_{8}(l)\) (coefficient \(1\) can be left blank as per instruction, so the filled - in boxes: first box \(2\), second box (left blank as \(1\) i…
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balance the chemical equation using the smallest possible whole number …
2, 3, 1
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balance the chemical equation using the smallest possible whole number …
2 (for HI), 1 (for \(H_2\)), 1 (for \(I_2\))
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question 6 1 pts donald: be careful with that chemical. it can _ your s…
harm
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1. what are the rows of the periodic table called? 2. what do they tell…
1. Periods 2. The number of electron shells of an element's atoms 3. Groups 4. The number of valence electrons (for main - group elements) and similar chemical properties 5. Lithi…
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12. which element is more reactive: sodium (na) or chlorine (cl)?
Sodium (Na) is more reactive.
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correct the text by inserting or removing commas. there should be a tot…
Organic fruits and vegetables, unlike conventionally grown ones, are not treated with pesticides. Still, it is necessary to wash them under running water.
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how does the law of conservation of mass apply to this reaction: al + 3…
A. Hydrogen and chlorine need to be balanced. There is an equal amount of aluminum on each side.
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part 4: fill in each arrow with the correct phrase word bank: atomic ra…
- **Horizontal arrow (left - to - right)**: atomic radius decreases, ionization energy increases, electronegativity increases - **Vertical arrow (top - to - bottom)**: atomic radi…
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how does the law of conservation of mass apply to this reaction: $c_{2}…
C. The equation needs to be balanced. There are fewer oxygen atoms in the equation than hydrogen or carbon.
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in the reaction _ al + 3o₂ → 2al₂o₃, what coefficient should be placed …
D. 4
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in the reaction __h₂ + n₂ → 2 nh₃, what coefficient should be placed in…
3
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1. how many valence electrons does lithium (li) have? answer here 2. ho…
1. 1 2. 4