Chemie
Chemische Reaktionen, Stöchiometrie, Molekülstrukturen und Elementeigenschaften.
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use the periodic table above to locate where the noble gases are locate…
Group 8A
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use the following to answer questions 99 - 102: use the periodic table …
Noble gases are located in the column labeled 8A (Group 18) of the periodic table, at the far - right end of the main - group elements (after the 7A group).
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which of the following is an example of a physical property? corrosiven…
lead becomes a liquid when heated to \( 601^\circ\text{C} \)
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how many milliliters is 0.005 l? 0.5 ml 5 ml 0.50 ml 0.000005 ml 200 ml
5 mL (corresponding to the option: 5 mL)
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an organic liquid has a density of 1.2 g/cm³. what is the mass of a 35.…
42 g (corresponding to the option "42 g")
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iron has a density of 7.86 g/cm³. the volume occupied by 55.85 g of iro…
7.11 $cm^{3}$ (corresponding to the option "7.11 $cm^{3}$")
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liquid nitrogen boils at -195.8°c. express the boiling point of liquid …
77.4 K (corresponding to the option "77.4 K")
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lead melts at 601.0°c. what temperature is this in °f? 302°f 365°f 1,05…
1,114°F (the option with "1,114°F")
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use the balanced equation, $4\\ce{al} + 3\\ce{o_2} \ ightarrow 2\\ce{al…
16.8
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2. ionic compound names. write the correct ionic compound name for each…
Lithium fluoride --- ### Corrections for existing answers: - $\text{CaI}_2$: Calcium iodide (correct spelling) - $\text{Sr}_3\text{P}_2$: Strontium phosphide (correct anion name) …
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7 multiple choice 1 point element x has a half - life of 50 years, a fo…
2 (corresponding to the option with value 2)
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use the balanced equation, $2\\ce{no} + \\ce{o_{2}} \ ightarrow 2\\ce{n…
6.82 (or 6.8 g, depending on significant figures; 12.8 has 3 sig figs, so 6.82 g)
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wine is produced by the fermentation of grapes. in fermentation, the ca…
\boxed{64} (or 65? Wait, maybe I made a mistake. Wait, 0.70 mol glucose, ratio 2:1, so 1.40 mol ethanol (since 0.70 has two decimal places? No, sig figs: 0.70 is two sig figs, so …
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notes: ionic bonding - ionic bonds form between a positive ion and a ne…
| Elements in ionic compound | Total positive charges | Total negative charges | Ionic Compound formula | |-----------------------------|------------------------|-----------------…
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use the balanced equation for the incomplete combustion of c₂h₄ to answ…
21 mol
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how many moles of c₂h₄ are needed to form 0.92 mol of co₂? 0.46 mol c₂h₄
\( 0.46 \) mol
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part 3 of 3 how many moles of c₂h₄ are needed to form 0.92 mol of co₂? …
\( 0.46 \) mol \( \ce{C2H4} \) (assuming mole ratio 1:2 between \( \ce{C2H4} \) and \( \ce{CO} \))
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part 2 of 3 how many moles of c₂h₄ are needed to form 0.65 mol of h₂o? …
\( 0.325 \)
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use the balanced equation for the incomplete combustion of c₂h₄ to answ…
21
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determine the number of grams found in 4.9 mol of li₂s. hint: you must …
\( 4.9 \cdot 45.95 \) g (the last option: \( 4.9 \cdot 45.95 \) g)
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determine the number of grams found in 4.4 mol of co₂. hint: you must f…
\( 4.4\cdot44.01 \, g \) (the last option)
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part 2 of 2\ 3.75 g of methanol (ch₄o)\ 3.75 g ch₄o = \\square mol ch₄o
\( 0.117 \) (or more precise \( \approx 0.117 \))
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how many moles are contained in each of the following? be sure each of …
0.542
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calculate the molar mass of (nh₄)₃po₃. 133.12 g/mol 97.02 g/mol 124.03 …
133.12 g/mol
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part 2 of 3 calcualte the molar mass of fe₂o₃? ○159.70 g/mol ○71.85 g/m…
159.70 g/mol (corresponding to the option: 159.70 g/mol)
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which of the following chemical formulas has a molar mass of 40.31 g/mo…
MgO (the chemical formula with molar mass 40.31 g/mol is MgO)
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patrick makes his solution and standardizes it using khp (204.22 g/mol)…
0.110 (or more precisely, let's do the calculation accurately: Moles of KHP = 0.7863 / 204.22 = 0.0038502 mol (approx) Volume of NaOH = 35.10 mL = 0.03510 L Molarity of NaOH = 0.0…
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patrick needs to make 100. ml of 0.15 m naoh in order to conduct an exp…
0.60
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petra titrates 50.0 ml of an orange juice sample with 65.0 ml of 0.20 m…
\( \approx 0.087 \, \text{M} \) (or more accurately, \( \frac{0.20 \times 65.0}{3 \times 50.0} = \frac{13}{150} \approx 0.0867 \, \text{M} \), rounded to two decimal places or sig…
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be sure your answer has the correct number of significant figures. \\(4…
For \(4.99\times10^{21}\) molecules: \(8.29\times 10^{-3}\space\text{mol}\) For \(2.0\times10^{23}\) molecules: \(0.33\space\text{mol}\)
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how many moles of carbon dioxide contain each of the following number o…
\( 44.2 \)
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orange juice contains the triprotic acid citric acid, h₃c₆h₅o₇. petra t…
3
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part 3 of 3 70.0 mol he = he atoms
\( 4.22 \times 10^{25} \) (rounded to three significant figures)
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65.24 ml of 0.12 m hcl reacts with 40.00 ml of nh₄oh solution to reach …
\(0.19572\) (or approximately \(0.20\) if rounded to two significant figures, but based on the given values, the more accurate value is \(0.19572\))
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household ammonia typically has a concentration of 5-10% nh₃ (nh₄oh) in…
1
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how many helium atoms are contained in each of the following number of …
\( 3.97 \times 10^{24} \) (or in the box, if we consider the format, maybe \( 3.97\times10^{24} \), but let's check the exact calculation. Wait, maybe the problem expects using \(…
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63.45 ml of 0.250 m ba(oh)₂ reacts with 0.750 m hno₃ and reaches the en…
42.3
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part 3 of 3 \\(\\ce{ch_{4}(g) + br_{2}(g) \ ightarrow cbr_{4}(s) + hbr(…
The balanced chemical equation is \( \boldsymbol{\text{CH}_4(g) + 4\text{Br}_2(g) ightarrow \text{CBr}_4(s) + 4\text{HBr}(g)} \)
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tamera has been assigned a titration between nitric acid and barium hyd…
1
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balance the following equations. remember to include states of matter. …
\( 2\text{CO}(g) + \text{O}_2(g) ightarrow 2\text{CO}_2(g) \) ### Part 2 of 3
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sum it up! types of rocks class ______ date ______ word bank fossilifer…
## Main Categories (Top to Bottom): 1. Igneous Rocks 2. Sedimentary Rocks 3. Metamorphic Rocks ## Subcategories (Top Section, Left to Right): 1. Extrusive Igneous Rock 2. Intrusiv…
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when khp reacts with a base, the anion kp- remains and the h+ reacts wi…
D. \( \text{KHP(aq)} + \text{NaOH(aq)} ightarrow \text{H}_2\text{O(l)} + \text{NaKP} \) (assuming D is the fourth option; if options are labeled as A, B, C, D, then D is the corre…
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6) what letter on the diagram indicates that the substance is boiling i…
To solve these questions, we typically refer to a heating - curve diagram (though the diagram isn't fully shown here, we can use general knowledge about phase changes and states o…
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2naoh(aq) + znbr₂(aq) → 2nabr(aq) + zn(oh)₂(s) element | number of atom…
Na: 4 O: 4 H: 4 Zn: 2 Br: 4 (Note: If the table is asking for the number of atoms in the reactants or products, the numbers would be 2, 2, 2, 1, 2 respectively, but based on the p…
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2c₄h₁₀(g) + 13o₂(g) → 8co₂(g) + 10h₂o(g) element | number of atoms c | …
For C: 8 For H: 20 For O: 26
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part 2 of 4 $\\ce{2h_{2}o_{2}(aq) -> 2h_{2}o(l) + o_{2}(g)}$ | element …
For H: 4; For O: 4
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ammonia (nh₃) chemically reacts with oxygen gas (o₂) to produce nitric …
\(0.68 \, g\)
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ammonium phosphate $\\ce{(nh_{4})_{3}po_{4}}$ is an important ingredien…
$\boldsymbol{9.1\ \text{g}}$
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a copper atom has a mass of $1.06 \\times 10^{-22}$ g and a penny has a…
\( 63.8 \) g ### Second Question: Moles of copper atoms in a penny
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a brick has a mass of 4.0 kg and the earth has a mass of 6.0×10²⁷ g. us…
\(2.4\times 10^{27}\space g\) ### Second Sub - Question: How many moles of bricks have a mass equal to the mass of the Earth?
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a major component of gasoline is octane ($ce{c_{8}h_{18}}$). when liqui…
\(0.51\ \text{mol}\) (or \(5.1 \times 10^{-1}\ \text{mol}\), but \(0.51\ \text{mol}\) is more direct)
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green plants use light from the sun to drive photosynthesis, a chemical…
$2.0\ \text{mol}$
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green plants use light from the sun to drive photosynthesis, a chemical…
$\boxed{2.0\ \text{mol}}$
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balance the chemical equation below using the smallest possible whole n…
\( \text{CH}_3(\text{CH}_2)_3\text{CH}_3(l) + 8\text{O}_2(g) ightarrow 5\text{CO}_2(g) + 6\text{H}_2\text{O}(g) \) (or with the formula written as \( \text{C}_5\text{H}_{12}(l) + …
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the chemical formula for t - butanol is: \\((\\text{ch}_3)_3\\text{coh}…
74.12
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the chemical formula for diethyl amine is: \\(\\left(\\mathrm{ch}_3\\ma…
\(73.14\)
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which component is reduced in the reaction below? 2na + s → na₂s na in …
S in \( \text{Na}_2\text{S} \) (the option: S in \( \text{Na}_2\text{S} \))
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the chemical formula for calcium hydroxide is: ca(oh)₂ calculate the mo…
$74.10\ \text{g/mol}$
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the chemical formula for potassium iodide is ki. a chemist determined b…
$1.66\ \text{g}$
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the chemical formula for potassium iodide is ki. a chemist determined b…
1.66
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the chemical formula for sodium bromide is nabr. a chemist measured the…
0.0720 mol
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the concentration of lactic acid in the yogurt sample is 0.01 m. what m…
$3.6\times 10^{-2}$ (so the first box is 3.6 and the second box is -2)
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the diprotic acid lactic acid is produced as a result of anaerobic resp…
\( 2.04 \times 10^{-2} \) (or more precisely \( 2.04375\times 10^{-2} \))
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30.0 ml of hno₃ requires 22.10 ml of 0.22 m ca(oh)₂ to reach the endpoi…
\(0.32\space M\) (or more precisely \(0.324\space M\))
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quentin titrates nitric acid with calcium hydroxide. balance the equati…
2
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44.00 ml of 0.50 m h₂so₄ reacts with 0.35 m lioh and reaches the endpoi…
\( 126 \) (or \( 125.7 \)) mL (Note: Depending on rounding, 126 or 125.7 is acceptable. If precise, \( \approx 125.7 \) mL, or 126 mL when rounded to whole number.)
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samuel has been assigned a titration between lithium hydroxide and sulf…
2
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standardization of sodium hydroxide with oxalic acid dihydrate titratio…
0.7102 M
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hc₂h₃o₂ + naoh → nac₂h₃o₂ + h₂o the concentration of the hc₂h₃o₂ was de…
\( 1.62 \) (or more precisely \( 1.6214 \))
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vinegar contains acetic acid. you titrate a vinegar sample with naoh of…
\(1.08\) (or more precisely \(1.080\))
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standardization of sodium hydroxide with khp titration procedures a gra…
I and IV
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if we have a sample of silicon (si) atoms that has 14 protons, 14 elect…
silicon-32
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all atoms of the element potassium have 19 protons. one of the most sta…
20 (B. 20)
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scientists are working with a liquid that is made of only one type of a…
The liquid contains only one element.
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what is the purpose of an indicator in a titration experiment? to mix t…
C. to determine the end point
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which of the following can be utilized to calibrate standard solutions?…
D. primary standard
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what is the end point in a titration? the point where the indicator cha…
A. The point where the indicator changes color.
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what instrument is used as the reaction vessel in a titration experimen…
B. beaker
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Question was provided via image upload.
Approximately \( 142 \, g \) (or \( 141.93 \, g \)) ### Question 27:
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what is the purpose of a stirring bar in a titration setup? to mix the …
A. to mix the solution evenly
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create complex mathematical models to represent chemical concepts. ance…
\( \approx 68.4 \, \text{g} \) (or more precisely, \( \approx 68.3 \, \text{g} \) if using more precise Avogadro's number) ### Problem 25: Determine the number of formula units of…
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2hcl + na₂co₃ → h₂o + co₂ + 2nacl he mixes exactly 235.0 ml of 0.600 m …
HCl and \( \text{Na}_2\text{CO}_3 \) are both used completely.
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18. classify each reaction below using one of the 5 reaction types: syn…
DR #### Part b
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he adds 45.0 ml of 0.200 m kmno₄ to excess ethene (c₂h₄). what mass of …
\boxed{0.782} (Wait, but maybe the correct answer is 0.782 g, but let me check again. Wait 86.94 * 0.009 = 0.78246, so with three significant figures, 0.782 g. Alternatively, mayb…
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kai creates his potassium permanganate solution and combines it with et…
3. \( \ce{K+} \)
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kai wants to create 0.250 l of 0.200 m potassium permanganate solution.…
7.90 (or 7.902)
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what is the concentration of the compound kmno₄ in the particle model s…
The concentration of \( \text{KMnO}_4 \) is \( \boldsymbol{0.2\ \text{M}} \) (or \( 0.2\ \text{mol/L} \)).
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what is the concentration of the compound kmno₄ in the particle model s…
# Explanation: ## Step1: Count the number of \( K^+ \) and \( MnO_4^- \) ions From the particle model, count the gray ( \( K^+ \)) and purple ( \( MnO_4^- \)) particles. Let's say…
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what is the electrolyte capacity of the compound in the particle model …
1
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6. zns + alp → zn₃p₂ + al₂s₃
The balanced chemical equation is \( \boldsymbol{3ZnS + 2AlP ightarrow Zn_3P_2 + Al_2S_3} \).
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2. kbr + cl₂ → kcl + br₂
$$2\text{KBr} + \text{Cl}_2 ightarrow 2\text{KCl} + \text{Br}_2$$
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what volume, in ml, of 0.35 m ca(no₃)₂ is required to completely react …
\( \boxed{107} \)
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25 ml of hydroiodic acid generates 1.20 l of h₂ gas at stp conditions w…
\( \approx 4.28\ M \) (or more precisely, using exact calculations: \( \frac{2\times1.20}{22.4\times0.025}=\frac{2.4}{0.56}\approx4.2857\ M \))
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how many grams of mg(oh)₂ form when 75.0 ml of 0.60 m naoh react with e…
1.31
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what volume of vinegar is required to generate 945 ml of co₂ gas at stp…
\( 50.7 \) mL (or approximately 51 mL depending on rounding during steps)
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how many grams of al are needed to produce 0.450 l of 1.6 m alcl₃? 2al …
\( \approx 19.4 \) (or 19.43) grams
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which measurement is more precise? 0.25 grams 1.25 grams 0.005 grams 0.…
0.005 grams
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eugene describes the physical property of a material as \sweet and flor…
odor
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water is made of two hydrogen atoms and one oxygen atom bonded together…
Atoms remain bonded to each other in physical changes.
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what happens when a substance undergoes a physical change? some physica…
Some physical properties change, but the substance keeps its identity.