化學
化學反應、化學計量、分子結構與元素性質。
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what is the bond angle in the structure? (options: 180, 109.5, 120; ima…
109.5
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what is the shape of the following molecular structure? options: trigon…
T - shape
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what is the bond angle for scl₆? options: 109.5, 104.5, 90, 107, 120; i…
90 (corresponding to the option with value 90)
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use the list to answer the question. - potassium, group ia - calcium, g…
D. potassium and iodine
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fluorine has 7 valence electrons. which charge is its ion likely to hav…
A. \(1^-\)
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hydrogen-hydrogen single bond/s are broken and —— carbon-hydrogen singl…
2; 8 (matching the teal option: 2; 8)
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which information about an atom can a period number give you? (1 point)…
A. how many energy levels it has
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which of the following illustrations shows a tetrahedral geometry?
The illustration with the yellow border (the top - most one) shows a tetrahedral geometry.
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when moving across a period from left to right in the periodic table (e…
B. Valence electrons increase by one.
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which method is not used to separate a mixture of sand, water, and salt…
D. Magnetic attraction
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draw a lewis structure for carbonate, co₃²⁻. then carefully compare you…
The correct option is the green - colored one (the fourth option from the top) with the Lewis structure showing a carbon atom double - bonded to one oxygen (with 2 lone pairs), si…
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based on the naming rules for ions, which of the following is a negativ…
D. chloride
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after separating the sand, which method would you use to separate the s…
C. Evaporation
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what is the shape of the following molecular structure? t-shape trigona…
Blue. Trigonal Pyramidal
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which method would you use first to separate sand from a mixture of san…
B. Filtration
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question 7 7/10 which of the following is an example of filtration? usi…
B. Separating noodles from water
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6/10 what is the purpose of a filter in the filtration method? to magne…
D. To separate solids from liquids (assuming the options are labeled A - D with D being the last option "To separate solids from liquids")
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in the example of separating salt from water using evaporation, what is…
D. Salt crystals
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4/10 what happens to the liquid in the evaporation method? it turns int…
A. It turns into a gas
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question 2 2/10 which tool is used in the sifting method? scroll more e…
B. Sieve (assuming the option with "Sieve" is labeled as B, following the order in the image where Sieve is the second option)
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type the correct answer in the box. round your answer to the nearest th…
14.007
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select all the correct locations on the image. in this diagram, which s…
The two blue particles labeled "E" (the electrons orbiting the nucleus).
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1/10 what is the basis for choosing a method to separate a mixture? che…
4. Physical properties
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the following electron configurations belong to which elements: 11) 1s²…
Sodium (Na) ### Question 12
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7. check the box if the statement describes the atom model. proposed by…
ing (checking boxes): - For the first (plum - pudding) model: Check “negative electrons floating in a ‘soup’ of positively charged material” and “proposed by J. J. Thomson”. - For…
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read the excerpt from ovid’s \pyramus and thisbe\, the blood leaped hig…
The figurative language describes the violence of the scene.
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select all the correct images. select the atomic models that belong to …
The atomic models that belong to the same element are the top - right model (with 1 proton, 1 neutron, 1 electron) and the bottom - left model (with 1 proton, 2 neutrons, 1 electr…
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5 type the correct answer in the box. calculate the density of the subs…
0.7
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select the correct answer in an experiment, lydia added 50 grams of sug…
A. A physical change took place during this experiment.
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select the correct answer. a student places a sample of white sodium bi…
D. It is not sodium bicarbonate.
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e to the correct location. properties as intensive or extensive. mass d…
### Intensive Property: - density - color - freezing point ### Extensive Property: - mass - volume
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chemical reactions that release energy are called ________ reactions. m…
C. exergonic (assuming the third option is labeled C, with the text "exergonic")
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the original molecules that enter a chemical reaction are called multip…
B. reactants (assuming the second option is labeled B; if the options are labeled differently, adjust the label but the text is "reactants")
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entropy is a measure of ______ in a closed system. multiple choice diso…
A. disorder
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which choice identifies the correct limiting reactant and correct reaso…
O₂: because it has the lower theoretical yield
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which choice identifies the correct limiting reactant and correct reaso…
O₂ because it has the lower theoretical yield
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which choice identifies the correct limiting reactant and correct reaso…
C. NaCl because it has the lower theoretical yield (assuming the third option is labeled C; if the original options have different labels, adjust accordingly to match the option w…
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which choice identifies the correct limiting reactant and correct reaso…
A. \( \text{H}_2 \) because it has the lower theoretical yield
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which choice identifies the correct limiting reactant and correct reaso…
Mg because it has the lower theoretical yield
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____ are the elements and compounds that go into a reaction. options (i…
Reactants
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reactants products molecules — are the elements and compounds that are …
Products
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the energy needed to start a reaction is called the promoting energy re…
D. activation energy (assuming the options are labeled A to D with A: promoting energy, B: reacting energy, C: starting energy, D: activation energy)
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at the end of this reaction, has energy been released or absorbed? (pot…
Released
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write the unabbreviated electron configurations of the following elemen…
\(1s^2 2s^2 2p^6 3s^2 3p^6 4s^1 3d^{10}\) ### 2) Iodine (I, atomic number 53)
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science 8 - pd(a-r) - 26-26 readiness test: introduction to matter fill…
mixture
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water, air, buildings, food, and everything visible and invisible has m…
D. matter
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building understanding one way to measure the amount of organic matter …
Long - term impacts relate to soil health and climate: - **Positive impacts (when soil carbon increases)**: Land use changes like “Crop to secondary forest” (+53%) and “Crop to pa…
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12. the number of significant figures in the measured value 0.00320 g i…
b. 3
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question 3 1 pts what element does the following noble gas configuratio…
A. rhodium
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question 2 1 pts what is the noble gas configuration of phosphorus? ne …
B. $[Ne] 3s^2 3p^3$ (assuming the second option is labeled B; if the original labels were different, adjust the label but keep the configuration. From the image, the selected opti…
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11. to two significant figures, the measurement 0.0255 g should be repo…
c. 0.026 g
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question 1 1 pts how does the noble gas configuration shorten the elect…
C. By putting the previous noble gas in front of the remaining configuration (assuming the options are labeled A, B, C, D with C being the third option as described)
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6. 0.25 g is equivalent to a. 250 kg. b. 250 mg. c. 0.025 mg. d. 0.025 …
b. 250 mg
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select the correct answer. sodium bicarbonate is the chemical name for …
C. There are three atoms of oxygen in sodium bicarbonate
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select the correct answer. a scientist conducts a chemical reaction. at…
C. The mass equals 11.7 grams because the system is closed.
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is this chemical stable under normal conditions? what type of substance…
To answer these questions, we need to know the specific chemical in question. Chemical stability and incompatible substances depend on the chemical's identity (e.g., its molecular…
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which material is the limiting ingredient if you have 12 cups of oats, …
walnuts (the option with "walnuts" as the text)
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which material is the limiting ingredient if you have 24 cups walnuts, …
A. pecans
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which material is the limiting ingredient if you have 4 pieces of sourd…
A. cheddar cheese
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which material is the limiting ingredient if you have 2 cans of tomatoe…
tomatoes
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how are nonmetals different from metals? recall that metals have luster…
Nonmetals are poor conductors of electricity and thermal energy. Solid nonmetals (at room temperature) have no luster. Many nonmetals are gases at room temperature. They are not d…
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select the correct answer. potassium chloride is a white solid used in …
A. KCI
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select the correct answer. carbon tetrachloride is a toxic liquid. a ca…
D. CCl₄
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select the correct answer. nitrous oxide is the chemical name for \laug…
B. two nitrogen atoms and one oxygen atom
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part ii: atom screen 1. click on the + sign for each of the boxes (elem…
Protons and neutrons ### Question 3: Play until you discover which particle(s) determine(s) the name of the element you build. Which particle is it?
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3. fill in the blanks in the following table | substance | mass (g) | v…
| Substance | Mass (g) | Volume (\(cm^{3}\)) | Density (\(g/cm^{3}\)) | |-----------|----------|---------------------|------------------------| | X | 10.0 | 20.0 | \(0.5\) | | Y |…
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air pollution global agreements several laws have evolved to address ai…
the United States
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air pollution global agreements several laws have evolved to address ai…
B. air pollution
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the melting point of an element is 5 times the melting point of radon. …
The melting point of the element is \(-350\) degrees Celsius.
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7 multiple choice 1 point make the following conversion (1g = 1000 mg) …
A. 9.231 g
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complete the names of these compounds. formula\tname fecl₂\tiron scl₂\t…
To solve this, we analyze each compound: ### For $\boldsymbol{FeCl_2}$: Iron (Fe) can have multiple oxidation states. In $FeCl_2$, Fe has a +2 oxidation state. When naming ionic c…
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what is the density an 84.7 g sample of an unknown substance if the sam…
D. 1.7 g/cm³
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which statement correctly describes glucose (c₆h₁₂o₆)? ○ it is made of …
It is a compound made of twenty - four total atoms.
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what quantity does the measurement 37 mmol represent? ○ speed ○ volume …
C. amount
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what volume would be occupied by 7.75 g of the substance with the densi…
4.53 $\text{cm}^3$ (the option with this value and unit, i.e., the third option: 4.53 $\text{cm}^3$)
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looking at the graph, what is the independent variable? vapour pressure…
Temperature
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basic atomic structure worksheet 1. the 3 particles of the atom are: a.…
a. Proton b. Neutron c. Electron Their respective charges are: a. \(+\) (positive) b. Neutral (no charge) c. \(-\) (negative) ### Question 2
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there are four common oxoanions of iodine and two common oxoanions of n…
- $\ce{IO_4^-}$: periodate ion - $\ce{IO_3^-}$: iodate ion - $\ce{IO_2^-}$: iodite ion - $\ce{IO^-}$: hypoiodite ion - $\ce{NO_3^-}$: nitrate ion - $\ce{NO_2^-}$: nitrite ion
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how many ml of liquid are in this burette? image of a burette with mark…
20.38 mL (the option: 20.38 mL)
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the density of copper is listed as 8.94 g/cm3. two students each make t…
D. Student B is more accurate and precise than student A
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a certain sample with a mass of 4.00 g is found to have a volume of 7.0…
\( 0.57 \) (the option with text "0.57")
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what quantity does the following measurement represent: 9.4 g/mol ○ spe…
B. molar mass (assuming the options are labeled with letters, and the correct option is the one with "molar mass")
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the chemical trimethylamine n-oxide not only gives fish their fishy sme…
B. As a result
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question 30 of 39 determine the name or formula for each polyatomic ion…
carbonate ### For the name "nitrite ion":
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motor oil would float on top of mineral oil densities of some common li…
False
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give the systematic names of these compounds. spelling counts. cui(s): …
s: - $\ce{CuI(s)}$: copper(I) iodide - $\ce{Fe2O3(s)}$: iron(III) oxide - $\ce{CoF2(s)}$: cobalt(II) fluoride - $\ce{FeO(s)}$: iron(II) oxide
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a scientist is conducting an investigation that involves water, silver,…
B. They are each made of matter. Some are compounds and some are elements. They all contain atoms.
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time doth transfix the flourish set on youth and delves the parches in …
by personifying time as cruel and destructive
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determine the formulas for these ionic compounds. copper(i) bromide: co…
$CuBr$ ### copper(I) oxide:
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true or false? water is the only natural substance that is found in all…
A. true
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question 27 of 39 what is the chemical formula for the compound formed …
For the compound between sodium and bromine: \(NaBr\) For the compound between sodium and selenium: \(Na_{2}Se\)
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general chemistry 4th edition mcquarrie • rock • gallogly university sc…
- Metal: $\ce{Tl}$, $\ce{Ga}$, $\ce{Bi}$ - Semimetal (metalloid): $\ce{Sb}$, $\ce{Ge}$ - Nonmetal: $\ce{Se}$, $\ce{S}$
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classify each compound as an ionic compound or a molecular compound. io…
Ionic compounds: AgI, BaO Molecular compounds: CS₂, CCl₄
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for each element, identify the charge of its most common ion. i ○ +3 ○ …
s: - I: -1 - Rb: +1 - O: -2 - Al: +3
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question 23 of 39 metals and nonmetals can react with each other to for…
- A potassium atom \(\boldsymbol{\text{loses}}\) \(\boldsymbol{\text{1 electron}}\) to form a \(\boldsymbol{\text{K}^+}\) (potassium) ion. - A sulfur atom \(\boldsymbol{\text{gain…
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choose the correct answer. what is one of the characteristics of the tr…
B. high density of air molecules
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why do garages usually have low air quality? they are outside. chemical…
B. Chemicals are stored in garages.
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identify the missing information for each atom or ion. note that the at…
s: ### First Part: number of neutrons: \( \boldsymbol{43} \) number of protons: \( \boldsymbol{34} \) number of electrons: \( \boldsymbol{36} \) ### Second Part: element symbol: \…
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how many protons are in an ion with 54 electrons and a −1 charge? numbe…
53 ### Second Sub - Question: How many total electrons are in a $\ce{Sr^{2+}}$ ion?
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what is the charge on a hypothetical ion with 45 protons and 49 electro…
The charge on the ion is \(-4\) (or we can say the ion has a charge of \(4-\) as it has 4 more electrons than protons).