Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
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practice: isotope calculations #2 1. complete the following table. nucl…
| Nuclear Notation | Atom or Ion? | Atomic # | Mass # | # of Protons | # of Neutrons | # of Electrons | |---|---|---|---|---|---|---| | $^{24}_{11}Na$ | Atom | 11 | 24 | 11 | 13 |…
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how many protons, neutrons, and electrons are in krypton? p = 36, n = 8…
P = 36, N = 48, E = 36 (the second option)
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question 8 (1 point) (02.02 lc) use the periodic table to match each of…
1. c 2. a 3. b ### Question 9
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how many protons, neutrons, and electrons are in lead (pb)? p = 207, n …
P = 82, N = 125, E = 82
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question 5 (1 point) (02.02 mc) helium (he), oxygen (o), carbon (c) flu…
- Question 5: d. Fluorine and chlorine, because they are both halogens - Question 6: d. Neon and argon, because they are both noble gases - Question 7: 1. b 2. c 3. a
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how many protons, neutrons and electrons are in boron? p = 10, n = 5, e…
P = 5, N = 5, E = 5
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(02.02 lc) mendeleev used his arrangement of elements in order of incre…
1. a. True 2. a. True 3. b. False 4. b. Magnesium (Mg), because they are both alkaline earth metals
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it protects against: dangerous substances cold and hot objects moving m…
Hazardous substances. Fire Moving machine parts. Cold and hot objects.
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7. the effective nuclear charge, ( z_{eff}), experienced by valence ele…
7. A. Increases 8. No correct core - electron option given; A. group 3A 9. C. Na and F 10. B. The element belongs in row 3 of the periodic table and is classified as a noble gas (…
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multiple - choice question how is the atomic mass determined? its the s…
B. add the number of protons and neutrons
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6. calculate the atomic mass of the unknown element. then identify the …
Problem 6: Atomic mass is approximately 186.21 amu, element is Rhenium (Re). Problem 7: Atomic mass is approximately 115.81 amu, element is Indium (In).
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good safety footwear is provided with: steel toe cap difficult to penet…
- The high top shoe offers more support and protects the Achilles tendon. - The low top shoe is suitable for people that need to kneel down a lot. - Leather safety boots are mainl…
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an atom’s emission of light with a specific amount of energy confirms t…
electrons emit and absorb energy based on their position around the nucleus
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what does the atomic number equal in a neutral atom? the number of prot…
the number of protons and also the number of electrons
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good safety footwear is provided with: steel toe cap difficult to penet…
Oil resistant., Soles that provide good grip., Steel toe cap., Nearly impenetrable.
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which subatomic particles determine the overall charge of an atom? □ pr…
B. protons and electrons
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data table 1: temperature reading for freezing point concentration of s…
A. If you increase the amount of salt in water, then it will result in a decrease in the water's freezing - point temperature.
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which subatomic particles determine the mass of an atom? protons, neutr…
protons and neutrons
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safety footwear protects the feet against dangerous substances, falling…
Hazardous substances, Getting caught or crushed, Falling objects
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essay questions. directions: below are essay questions you may encounte…
1. The reactivity increases when moving from an element with atomic number 10 (Neon) to atomic number 11 (Sodium). Neon is a noble gas with a stable electron configuration and low…
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safety glasses resemble ordinary glasses, but the lenses are made of ha…
A. False B. False C. True D. True E. True
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which subatomic particles have a positive charge? □ protons □ neutrons …
protons
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safety glasses resemble ordinary glasses, but the lenses are made of ha…
Welding helmet / visor, Goggles, Over - spectacles, Safety glasses, Face visor
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safety glasses and goggles with activities like drilling, grinding, wel…
Welding helmet / visor, Goggles, Over - spectacles
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with activities like drilling, grinding, welding and sanding, chips and…
Drilling, Welding, Grinding, Sanding
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1. what is the primary component of seawater? 2. name two major ions fo…
1. Water (H₂O) 2. Sodium (Na⁺), Chloride (Cl⁻) 3. A chemical reaction forming carbonic acid (H₂CO₃) 4. Reduces the availability of carbonate ions for shell - building 5. Photosynt…
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1. what is the primary component of seawater by volume? a) dissolved ga…
1. c) Water 2. d) Sodium and chloride 3. b) Increased levels of atmospheric carbon dioxide 4. d) Shellfish 5. a) It decreases
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vocabulary: match the vocabulary word to its definition. answer vocabul…
1. D. 2. C. 3. B. 4. F. 5. A. 6. E.
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which tool on the display settings menu controls the color - scheme of …
C. Environment
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4. an irregularly - shaped object is placed in a graduated cylinder alr…
6.5 × 10⁻¹ g/cm³
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a chemical substance has a decay rate of 7.3% per day. the rate of chan…
a) $N(t)=N_0e^{-0.073t}$ b) 417 g c) - 30.4 g/day d) 9.5 days
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a chemical substance has a decay rate of 7.3% per day. the rate of chan…
417
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a chemical substance has a decay rate of 7.3% per day. the rate of chan…
a) $N(t)=N_0e^{-0.073t}$ b) $416.82$ g c) $-30.43$ g/day d) $9.49$ days
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vocabulary: match the vocabulary word to its definition. 1. air and wat…
1. A. Air and Water Pollution 2. C. Urbanización 3. E. Changing the Flow of Water 4. B. Desertificación 5. A. Deforestation 6. F. Erosion
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physical properties can be used to compare and classify substances. the…
None of the provided options (melting point, density, thermal conductivity) correctly represent the physical property demonstrated by the process of sugar dissolving in water.
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accidental activation of airbags can cause severe injury. most accident…
Physical injuries caused by direct airbag strike or indirect strikes by the objects nearby that were set off by the airbag., Burn injuries caused by the heat released by the chemi…
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which kind of matter is each sample? sample 1 sample 2 sample 3 element…
Sample 1: Element Sample 2: Compound Sample 3: Compound
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to prevent accidental discharge, workers must follow the manufacturers …
There are chemicals inside an airbag. Chemicals are ignited by means of electricity, the chemical reaction generates gas which inflates the airbag, forming a cushion to damp the i…
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equipment and technology quick check which type of glassware would most…
D. a beaker
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1. einstein the dog weighs 74 pounds. how much does he weigh in grams? …
34000 grams 19% $3.73 \times 10^{17}$ inches
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which piece of glassware is cone shaped except for a cylinder - shaped …
B. Erlenmeyer flask
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question 1 - 5 scientists who study elements and how they interact are …
The structure and properties of elements like oxygen and iron
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of an initial amount of 2000 g of lead - 210, how much will remain in 1…
$35.5$
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review the claim and the two pieces of evidence. chewing gum can improv…
Evidence B does not come from a credible source. It is based on the opinion of one person who is not an expert and has not done research.
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consider this claim: chewing gum can improve our alertness and lower ou…
A. In a study of forty participants, those who chewed gum while performing stressful tasks had lower levels of anxiety and higher levels of alertness than those not chewing gum.
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14. how many total electrons does k have? a. 17 b. 18 c. 19 d. 20 15. h…
14. C. 19 15. A. 9 16. B. 10 17. 9
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9. how many electron shells does n have? a. 1 b. 2 c. 3 d. 4 10. how ma…
9. B. 2 10. B. 2 11. 7 12. 6 13. 8
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5. how many valence electrons does magnesium have? a 1 b 6 c 4 d 2 6. h…
5. D. 2 6. A. 7 7. A. 7 8. B. 2
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1. what is the periodic symbol for sulfur? a. s b. sa c. s d. su 2. wha…
1. C. S 2. A. Si 3. D. Potassium 4. A. Carbon
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19. which of the following is not a typical cause of anorexia nervosa? …
# Breve explicación: La anorexia nerviosa es un trastorno mental complejo. La baja autoestima, el deseo intenso de complacer a los demás y la falta de químicos reguladores del est…
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what has the greatest ionization energy? mg ca na k
Mg
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what has the greatest ionic radius? br k cl ar what has the greatest el…
1. Br 2. Cl 3. K 4. K
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what has the greatest atomic radius? ne mg ca fr what has the greatest …
1. What has the greatest Atomic Radius? Fr 2. What has the greatest Ionic Radius? Fr 3. What has the greatest Ionization Energy? Ne 4. What has the greatest Electronegativity? Mg
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what has the greatest atomic radius? ar s mg k what has the greatest io…
1. What has the greatest Atomic Radius? K 2. What has the greatest Ionic Radius? K 3. What has the greatest Ionization Energy? Ar 4. What has the greatest Electronegativity? S
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the meniscus is the lowest part of the curve, and that is where you tak…
# Explicación: ## Paso 1: Identificar la graduación del cilindro graduado El cilindro graduado tiene una graduación de 1 mL entre cada línea. ## Paso 2: Leer la posición del menis…
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what has the greatest atomic radius? o n si al what has the greatest io…
1. What has the greatest atomic radius? Al 2. What has the greatest ionic radius? O 3. What has the greatest ionization energy? O 4. What has the greatest electronegativity? O
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what has the greatest atomic radius? he cl sr cs what has the greatest …
1. What has the greatest Atomic Radius? Cs 2. What has the greatest Ionic Radius? Cs 3. What has the greatest Ionization Energy? He 4. What has the greatest Electronegativity? Cl
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in a lab experiment, students had four samples of elements. they made o…
D
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fingerprint reliability and validity 1. in the 1995 test given to 156 f…
1. Variability and error potential among examiners. 2. Misidentified Mayfield's fingerprint; exonerated when real perpetrator identified. 3. Lack of standardization, subjectivity,…
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what has the greatest atomic radius? f ne ca k what has the greatest io…
1. What has the greatest Atomic Radius? - D. K 2. What has the greatest Ionic Radius? - A. F 3. What has the greatest Ionization Energy? - B. Ne 4. What has the greatest Electrone…
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20 multiple choice 10 points mucus, tears, saliva, and hair are all exa…
D. Mechanical barriers
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nh3 is nitrogen trihydride (ammonia) and bf3 is boron trifluoride. what…
Aluminum chloride - It does not have the prefix "tri -" since it is ionic.
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the alkali metals, found in group 1 of the periodic table, are very rea…
Elements in the same group have the same number of valence electrons. Sodium in group 1 has 1 valence electron and chlorine in group 17 has 7 valence electrons. Sodium donates its…
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what is a column called in the periodic table and what do the elements …
What is a column called in the periodic table: Group. What do the elements in each column have in common: The same number of valence electrons. Based on what the periodic table ca…
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significant digits are used in chemistry to show the ______________ of …
precision
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which nonmetal would an ion of ca²⁺ most likely ionically bond with in …
B. one atom of oxygen
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sodium ions are used by your body every time you move a muscle. the dif…
C. a sodium atom has one fewer electron.
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what is the answer expressed with the correct significant digits for: 7…
3.4 g/cm³
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the decomposition of dinitrogen tetroxide into nitrogen gas and oxygen …
B. $N_2O_4(g) ightarrow N_2(g)+2O_2(g)$
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what coefficients are needed to balance the chemical equation? nabr + c…
B. 2,1,2,1
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4al + 3o₂ → 2al₂o₃ question: in the reaction and the product(s) is/are …
D. aluminum oxide
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a solution with a range of ph of 0 - 6 is a base alkaline neutral solut…
D. ácido
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43. someone might not feel well after riding a fast elevator in a tall …
B. the semi - circular canals (rotational equilibrium)
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atomic structure 7 periods/rows. the number of energy levels/shells con…
The periodic table arranges elements by periods (rows) corresponding to energy levels. Metals, on the left of the "stair - step" line (except hydrogen), are conductors, malleable,…
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directions: use the periodic table to fill in the below chart. name 6.4…
| Element | Symbol | Atomic Number | # of Protons | # of Electrons | Atomic Mass | Rounded Atomic Mass | # of Neutrons (show work) | Period | | ---- | ---- | ---- | ---- | ---- | …
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directions: use a periodic table to find the information asked for belo…
1. Calcium: 20, Iron: 26, Gold: 79, Uranium: 92 2. Calcium: 40.08, Iron: 55.85, Uranium: 238.03, Copper: 63.55 3. Calcium: 20, Gold: 79, Copper: 29, Iron: 26 4. Gold: 79, Iron: 26…
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which of these illustrations best represents the particles in a gas? a …
For the first question: a For the second question: a, c, d, f
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put some tap water in two cups. stir a bit of table salt into one of th…
# Explicación: ## Paso 1: Comprender la conductividad eléctrica La sal disuelta en agua forma iones. Estos iones permiten el flujo de electricidad. ## Paso 2: Comparar los dos tip…
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50. baking soda is chemically known as: na₂co₃ nahco₃ caco₃ khco₃
B. NaHCO₃
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using the periodic table, what can you conclude about the classificatio…
C. Iodine is a nonmetal and is dull, brittle, poor conductor of heat and electricity, forms anions in aqueous solution, and is a solid at room temperature.
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48. chalk is mainly composed of: caco₃ na₂co₃ k₂co₃ mgco₃ 49. the formu…
48. $CaCO_3$ 49. $H_2O$
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46. the formula for potassium oxide is: ko k₂o k₂o₂ ko₂ 47. how many ox…
46. B. $K_{2}O$ 47. C. 12
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the diagram shown is an example of the element. a boron. b bromine. c n…
A. boron
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44. the formula of slaked lime is: cao ca(oh)₂ cah₂ caho₂ 45. sodium ox…
44. B. $Ca(OH)_2$ 45. B. $Na_2O$
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chapter 4.4 - 4.5 vocabulary: fill in the blank name: ____________ pd__…
1. Periodic Table 2. Group 3. Alkali Metal 4. Alkaline Earth Metal 5. Halogen 6. Noble gas 7. Transition Metal 8. Metal 9. Nonmetal 10. Metalloid 11. Law of Conservation of Mass 1…
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which elements will bond ionically with barium such that the formula wo…
B. Chlorine, iodine, and fluorine
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e - cigarette use can prevent the lungs from recovering properly from v…
- Question 13: True - Question 14: No cigarette, filtered or unfiltered, is truly safe - Question 15: Approximately 90%
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e - cigarette use can prevent the lungs from recovering properly from v…
Question 13: True Question 14: No cigarette, filtered or unfiltered, is truly safe Question 15: Approximately 90%
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this diagram represents the synthesis of nitrogen monoxide. write a bal…
$N_2(g)+O_2(g) ightarrow 2NO(g)$
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there is a 100% safe way to use tobacco. true false question 5 (1 point…
False False Leads to changes in brain chemistry
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when magnesium (mg2+) and fluorine (f1 -) combine in an ionic bond, the…
B. $MgF_{2}$
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during a physical science lab investigating chemical reactions, several…
C. 10 grams
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the element hydrogen has three naturally occurring isotopes, h - 1, h -…
1 proton, 2 neutrons, 1 electron (Option B)
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a calcium bromide compound is represented by which formula? a ca2br b c…
The formula for calcium bromide is $CaBr_{2}$, so the correct option is not shown in the provided description (assuming the correct one should be $CaBr_{2}$ among the choices in t…
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6. ____ displays use organic molecules that are self - illuminating and…
a. OLED
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the formation of lithium fluoride (seen here) is due to a a stronger pu…
B. increased stability in the completion of fluorine's outer shell.
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a student is told that both energy and mass must be conserved in every …
D. Gas escapes, indicating mass loss as it leaves the container.
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question 11 (3 points) 218 84 po → 0 -1 e⁻ + word bank: 218 bi at 85 83…
Blank 1: 218 Blank 2: At Blank 3: 85
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you are given two unknown solutions, a and b. one of the solutions cont…
A. A contains sugar and B contains salt, because salt is ionic and is a good conductor of electricity.
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which formulas and their respective names do not match? i) bao barium h…
A. (i) only