化学
化学反应、化学计量、分子结构与元素性质。
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a student brings a bottle of water into the lab and sets it near chemic…
1. D. All of the above 2. B. Read and understand all lab instructions before starting 3. C. Taste them to identify the substance
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which statements accurately describe matter? check all that apply. only…
B. Matter is made up of tiny particles called atoms., D. Atoms cannot be divided and still retain the properties of its original state.
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which piece of clothing is not appropriate for lab safety? * dangling j…
1. A. Dangling jewelry 2. A. 2500 mL 3. B. Wave your hand gently over the container toward your nose (wafting)
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you spill a small amount of chemicals on the lab bench. what should you…
First question: C. Notify the teacher and clean it with the proper spill kit. Second question: B. 5 g
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perform the calculation and use the correct number of significant figur…
$0.121$
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what does the first line of the poem mean? the author is addressing peo…
The author is speaking to her children in this poem.
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which of the following statement/s is/are true? a. glucose and galactos…
C. Galactose and mannose are isomers
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which of the following statement/s is/are true? a. glucose and galactos…
C. Galactose and mannose are isomers
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presence of a sunflower - shaped crystal on osazones test reveals the p…
A. Maltose
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which of the following statement/s is/are true? * a. glucose and galact…
A. Glucose and galactose are C - 4 epimers because their structures differ only in the position of the hydroxyl group at carbon 4.
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lactose, glucose and fructose test positive in benedicts test. what is …
B. Brick - red precipitate
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test specific for polysaccharides * bials test iodine reaction osazones…
B. Iodine reaction
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the chemical is also a radioactive isotope, which means it can be visua…
D. made viewable
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rank the following elements by increasing atomic radius. enter the numb…
1. Chlorine, Cl 2. Aluminium, Al 3. Potassium, K
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car batteries use solid lead and lead (iv) oxide in sulfuric acid to pr…
10 moles
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question: 28 of 36 form a 11.0: chemistry on - line test (cd: c) 28 ord…
Magnesium, Mg; Silicon, Si; Argon, Ar; Neon, Ne
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civics chapter 1 section 1 homework assignment what is an example of a …
D. Voting
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what is the charge on copper in cuf₂? a 1− b 2− c 1+ d 2+
D. 2+
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which of the following describes a compound that contains molecular cov…
A. does not conduct a current as a solid or as a liquid and sometimes dissolves in water
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25 below are labels of types of bonding that can occur between individu…
hydrogen bonding → dipole - dipole → London dispersion
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cfu: conservation of matter a student mixes two clear, colorless liquid…
It is a chemical change because the formation of a precipitate indicates a chemical change
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tyranny has the same or almost the same meaning as: absolutism scheme c…
A. absolutism
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name date group 17: halogens • group 17 valence electrons; form • most …
1. Metals, Non - metals, Metalloids 2. Metals, Non - metals 3. Group 18 (Noble Gases)
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9. three arrows hitting a target at a single spot but not the bulls eye…
9. b. Precision 10. c. Density 11. a. Scientific notation 12. c. Independent variable 13. b. Applied research 14. a. Theory 15. a. Model 16. b. Fahrenheit and milliliter
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which statement describes carbons unique bonding ability? carbon can bo…
Carbon can easily form 4 covalent bonds with other atoms
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chem ch 1 scientific method / measurement test - aug 2020 choose the be…
1. c. Chemistry 2. c. Mass 3. b. Kilogram 4. d. Mass divided by volume 5. c. Form a hypothesis 6. b. Circle 7. b. Inductive reasoning 8. a. Mass
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which molecules are considered organic? all natural those containing ph…
D. those containing carbon
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which statement best explains why carbon is present in so many kinds of…
It can form four covalent bonds
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what is the most important role of hydrogen bonding between water molec…
It enables water molecules to bond to each other.
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which statement is true about water molecules? water molecules move ran…
The oxygen atom has a slight negative charge
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do the following statements describe a chemical or physical change? a f…
1. A. chemical 2. A. chemical
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do the following statements describe a chemical or physical property? u…
1. chemical 2. physical
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for each chemical formula, classify as a pure compound, pure element, o…
$Br_2(g)$: pure element $NaNO_3(aq)$: mixture $NaNO_3(s)$: pure compound $P_4(s)$: pure element
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three students (a, b, and c) are asked to determine the volume of a sam…
Student B's measurements demonstrate higher precision than Student C. Student C has the least accurate measurement.
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three students (a, b, and c) are asked to determine the volume of a sam…
Student B's measurements demonstrate higher precision than Student C.
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substance classification hcl(aq) select nano₃(aq) pure compound p₄(s) p…
HCl(aq): mixture NaNO₃(aq): mixture P₄(s): pure element N₂(l): pure element
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consider the following metals and their densities: element density (g/m…
platinum
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the density of ethanol, a colorless liquid that is commonly known as gr…
17.4 g
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read the lines from the tide rises, the tide falls. along the sea - san…
It strengthens the connection between the two lines.
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consider the following metals and their densities: | element | density …
platinum
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consider the following metals and their densities: element density (g/m…
magnesium
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the density of ethanol, a colorless liquid that is commonly known as gr…
$25.8$
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mercury is a shiny liquid. calculate its density if 1417.5 g of the sub…
$13.5$ g/mL
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the following shows an experiment used to determine the density of a ga…
$0.0064\ g/mL$
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multiple choice question what is the magnitude of the average momentum …
Zero
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multiple choice question why is the net force due to the pressure exert…
The parallel component cancels out due to the random orientation of the motion of the atoms and molecules.
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multiple choice question what causes the pressure of a static fluid in …
The gravitational force caused by the Earth
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abbey always gets zits on her chin and she cant figure out the best met…
1. Incorrect. Independent variable: Type of face - wash product (soap and water, acne face - wash, organic oils). 2. Imprecise. Dependent variable: The number of zits on her chin.…
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unit 3 properties > lesson 6 solutes and solvents back to intro page so…
removing solution from the container
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untt 3 properties > lesson 6 solutes and solvents back to intro page so…
The cocoa was mixed with hot water, but some cocoa settled as it cooled because the solubility went down.
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solutes and solvents quick check use the graph to answer the question w…
As temperature rises, gas particles are moving faster and may leave the solution.
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solutes and solvents quick check which option is a microscopic property…
B. polarity
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solutes and solvents quick check which substance is an example of a non…
B. vegetable oil
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question 2 of 10 jason works for a restaurant that serves only organic,…
D. Green business
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you are allowed to enter the chemical preparations/storage area any tim…
1. B. False 2. B. False 3. D. none of the above
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if a laboratory fire erupts, immediately notify your instructor run for…
1. notify your instructor 2. an open flame 3. True
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question 9 1 pts write the names (all lowercase) for three diatomic ele…
hydrogen, oxygen, nitrogen
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question 8 1 pts what is the state of matter for each of the following …
Si: Solid Hg: Liquid K: Solid $F_2$: Gas
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question 5 select all features of a mixture. represented by an element …
consists of multiple compounds/elements, groups in a sample are different
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question 4 1 pts state whether each of the following is a physical or c…
1. Physical change 2. Chemical change 3. Chemical change
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the scientific method of investigation quiz cp chemistry a o / module 1…
B. the scientific method
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3. jax designs an experiment to determine how the amount of sodium chlo…
the temperature at which the water boils
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1. jaz designs an experiment to determine how the amount of sodium chlo…
B. the amount of sodium chloride
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what is levitation? a levitation illusion is one in which a magician ap…
A. Use high-contrast color schemes
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2. the reaction a + b → c is first - order in both a and b. the reactio…
a. $[A]=2.0\ M$ b. $k = 0.30\ s^{-1}$
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a student is researching the negative health effects of processed foods…
The statistics from the research study
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test vi: provide which element is being described in each of the follow…
46. Gold 47. Silicone 48. Copper 49. Oxygen 50. Sodium 51. Chlorine 52. Mercury 53. Carbon (diamond form) 54. Lithium 55. Copper
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the diagram shows the relationship between two sets. a. use the diagram…
a. C. Some college students are not chemistry majors. b. C. False. Its negation is "All college students are chemistry majors."
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test iii. identify whether each element below is classified as metal, n…
21. Metal 22. Metal 23. Metal 24. Metal 25. Metal 26. Metal 27. Non - metal 28. Non - metal 29. Metalloid 30. Metalloid
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test ii: write the name of the element located in the given group and p…
All elements cannot be determined as periods 11 - 20 are not part of the standard periodic table.
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test iii. identify whether each element below is classified as metal, n…
21. Mercury - Metal 22. Erbium - Metal 23. Sodium - Metal 24. Polonium - Metal 25. Cerium - Metal 26. Bismuth - Metal 27. Hydrogen - Non - metal 28. Neon - Non - metal (Noble Gas)…
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what is a type of contaminant that can cause foodborne illness? chemica…
parasites
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which statements describe processes involved in the accretion of planet…
- Both involve the formation of solid particles from nebular materials. - Both involve the trapping of gases and the clumping of masses of matter. - Both involve the growing of ga…
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entering chemical expressions to enter chemical formulas, equations, an…
$C_{4}H_{10}$
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gabriella stops into a convenience store to find a healthy snack and se…
check the bottle's nutritional label to determine if all the ingredients are healthy
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oh- is used to represent which of these? a hydrogen ion a salt ion a hy…
a hydroxide ion
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¿los peligros químicos son siempre visibles? select the best option. si…
# Breve explicación: Los peligros químicos pueden ser gases, sustancias químicas invisibles o compuestos que no son visibles a simple vista, como ciertos ácidos o alcalis disuelto…
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which type of molecule has charges that are unevenly spread out causing…
polar molecules
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observe the burning candle. what can be said about the mass of the prod…
The mass of the new candle is THE SAME AS the mass of the burnt candle plus ALL of the products.
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a pharmacy technician observes a patient who is demonstrating aggressiv…
Withdrawal from a physical dependence of a controlled substance
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how many different atoms are involved in making up a molecule of pure o…
only one
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which of these makes up elements? atoms compounds cells
atoms
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(b) a tooth - whitening gel is to be tested for effectiveness. a group …
For first part: The remaining 42 adults receive the placebo gel., After the treatment period, compare the whiteness of the two groups., Randomly select 43 adults to be given the t…
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which of the following federal agencies should a pharmacy staff member …
Question 17: C. DEA Question 18: C. Witness controlled substance disposal
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how many grams of salt are needed to make 645 g of salt water that is 3…
$203.175\ g$
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a certain ore is 33.9% nickel by mass. how many kilograms of this ore w…
$0.0737$ kg
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foods that are high in calories but low in weight or volume are called …
B. high - energy - dense foods
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1. we use chemical formulas to represent individual molecules and group…
a. $CO_2$ b. $H_4O$ c. $O_6$ d. $N_6$ e. $H_8$
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1. we use chemical formulas to represent individual molecules and group…
a. $CO_2$ b. $C_2H_6$ d. $N_6$ e. $H_8$
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draw it! what does the big 2 in 2co2 mean? what does the little 2 in 2c…
- In 2CO₂, the big '2' means 2 molecules of carbon - dioxide; the little '2' means each CO₂ molecule has 2 oxygen atoms. - In 4H₂, the big '4' means 4 molecules of hydrogen; the l…
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7. calculate the specific heat for a substance if 58.0 joules are requi…
$0.39\ J/(g\cdot^{\circ}C)$
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2. cite evidence from the article to support the authors claim. article…
2. Water molecules were in the initial swirl but Earth's early conditions were not good for retaining surface water. Comets and asteroids can contain ice and could have delivered …
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explore directions: read the information below. then use the informatio…
There are two main hypotheses: 1. Icy comets deposited water on Earth's surface. 2. Earth was formed with water in its interior and supplies water to the surface via plate - tecto…
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this graph shows which of the following? there is positive evidence tha…
There is a positive correlation between the sale/consumption of organic food and the number of individuals diagnosed with autism between 1998 and 2007.
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sketch an atom label 4 protons in the nucleus. draw 5 neutrons in the n…
Beryllium (Be)
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sketch an atom label 8 protons in the nucleus. draw 8 neutrons in the n…
Oxygen (O)
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match the underlined antonym in each sentence to its corresponding voca…
1. limited - interminable 2. ignoring - pullulating 3. happiness - penitence 4. dry - saturated 5. join - bifurcate
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ecrivez le nombre correct basé sur le dessin. 1. étudiant(s) porte(nt) …
1. 1 2. 6; 1 3. 2 4. 3 5. 8; 7 6. 2
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if the haudenosaunee women who lead local clans believe their sachems a…
B. Checks and balances
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which of these statements describes a meta - analysis? the acceleration…
The statement "This systematic review of all studies on mental illness - related beliefs and attitudes in the general population was published before March 21, 2011. - Acta Psychi…