化学
化学反応、化学量論、分子構造、元素の性質。
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name: considering the heating systems below are two diagrams showing th…
1. **Same Molecule Traits**: Both use $H_2O$ molecules with identical 30°C average kinetic energy. 2. **Different Molecule Traits**: Groundwater may have dissolved minerals; heate…
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short for chlorofluorocarbons, cfcs are chemical compounds. scientists …
B. cause/effect
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3. which as the larger percent by mass of sulfur, h2so3 or h2s2o8? (0.5…
\(H_2SO_3\) ### Question 4
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hi, maya. when you submit this form, the owner will see your name and e…
$45.05\%$ ### Question 2
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look at the key and four images below. answer the reflection question, …
B. Hot Water (spread-out molecules) / Cold Water (tight, dense molecules)
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identifying rhyme scheme directions 1. read the following poems. 2. for…
### Rhyme Scheme (line by line): Mary had a little lamb: A Her fleece was white as snow: B And everywhere that Mary went: C The lamb was sure to go: D It followed her to school on…
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today i had a rotten day today i had a rotten day. as i was coming in f…
AABB
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my penmanship is pretty bad my penmanship is pretty bad. my printings p…
ABAB
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all my great excuses i started on my homework but my pen ran out of ink…
ABAB
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express your answer in kilograms per cubic meter. view available hint(s…
$5.23 \times 10^{3}$
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mr. brown the circus clown mr. brown, the circus clown puts his clothes…
AABB
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name unit 8 mixed practice complete each step for all of the following …
### Question 1: Dicarbon hexahydride reacts with oxygen gas to produce carbon dioxide and water #### Step 1: Translate to chemical equation Dicarbon hexahydride is \( C_2H_6 \), o…
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rhyme scheme directions 1. read the following poems. 2. for each poem, …
## Mr. Brown the Circus Clown Mr. Brown, the circus clown: A puts his clothes on upside down: B He wears his hat upon his toes: A and socks and shoes upon his nose: B Rhyme scheme…
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rhyme scheme directions 1. read the following poems. 2. for each poem, …
## Mr. Brown the Circus Clown Mr. Brown, the circus clown: A puts his clothes on upside down: B He wears his hat upon his toes: A and socks and shoes upon his nose: B Rhyme scheme…
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my cat #2 my cat is nice. my cat is fat. my cat likes mi i like my cat.…
Rhyme scheme: AB CB
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rhyme scheme directions 1. read the following poems. 2. for each poem, …
- My Cat #1 Rhyme Scheme: AABB - My Cat #2 Rhyme Scheme: AB CB
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rhyme scheme directions 1. read the following poems. 2. for each poem, …
### My Cat #1 - My cat is nice.: A - My cat likes mice.: A - My cat is fat.: B - I like my cat.: B - Rhyme scheme: AABB ### My Cat #2 - My cat is nice.: A - My cat is fat.: B - My…
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in this experiment, you will first change the temperature of the water …
How do water temperature and antacid tablet size affect the time required for an antacid tablet to dissolve?
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any molecules with a ph from 7 to 14
Bases (or alkaline substances)
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the only molecule that has a ph of 7
Water (H₂O)
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the only molecule that has a ph of 7
Water (H₂O)
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which of these are illegal or scam activities? check all that apply □ r…
- running a pyramid scheme - hacking to harm property - distributing a virus - hacking a computer
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balancing and types of reactions practice balance the equation: □al₂(so…
Balanced equation: $\boldsymbol{\ce{1Al2(SO4)3 + 3Ca(OH)2 -> 2Al(OH)3 + 3CaSO4}}$; Type of reaction: Double - Displacement (or Precipitation)
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balancing and types of reactions practice balance the equation: $square…
The balanced equation is $\boldsymbol{1}\ce{Ca(OH)2 + 1H2SO4 ightarrow 1CaSO4 + 2H2O}$ and the type of reaction is **Neutralization (Double - Displacement)**.
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be sure to read the information at the left before answering this quest…
in the atmosphere
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how is this substance classified? it has the formula nh₃. image of mole…
a compound
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which technique involves passing a mixture through a porous barrier to …
filtration
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what happens during the process of evaporation? liquid is added to diss…
Heat is applied to crystallize a dissolved solid and remove the liquid.
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which of these techniques can be used to effectively separate an undiss…
settling, then decantation
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what is the process that separates and crystallizes a dissolved solid, …
evaporation
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what technique would you use if you wanted to separate a mixture of iro…
magnetism
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what method would separate a mixture of iron filings and sugar most eff…
D. Use a magnet to attract the iron.
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what separation technique is illustrated in the picture? evaporation de…
evaporation
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what technique effectively separates mixtures of liquids that have diff…
distillation
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distillation of wintergreen mouthwash heat is applied gently to a solut…
wintergreen
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distillation of cherry-vanilla cola heat is applied gently to a solutio…
D. the sugar remaining in the flask
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water and alcohol are two liquids that mix completely but can be separa…
D. boiling point
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vinegar and water are liquids that mix completely together. which techn…
distillation
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based on the order the substances come out of the distillation, which s…
B. the vanilla ester
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which of these mixtures would best separate using distillation? solid s…
honey and tea
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what method is used to separate molecules of different polarities or at…
chromatography
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according to this chromatography strip, which dye color is most similar…
the red dye
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what separation technique is illustrated in the picture? decantation ch…
chromatography
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what separation technique is illustrated in the picture? options: filtr…
distillation
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determine which factors will increase the reaction rate and which facto…
Increase Reaction Rate: Increase temperature Increase surface area Add a catalyst Decrease Reaction Rate: Decrease concentration Decrease temperature Decrease surface area
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a dilute solution of water and milk is prepared. when tested, the solut…
colloid
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classify the following as a heterogeneous mixture (suspension), homogen…
homogeneous mixture (solution)
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classify the following as a heterogeneous mixture (suspension), homogen…
heterogeneous mixture (suspension)
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classify the following as a heterogeneous mixture (suspension), homogen…
heterogeneous mixture (suspension)
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classify the following as a heterogeneous mixture (suspension), homogen…
colloid
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classify the following as a heterogeneous mixture (suspension), homogen…
colloid
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classify the following as a heterogeneous mixture (suspension), homogen…
heterogeneous mixture (suspension)
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what term describes two or more substances that are physically but not …
mixture
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compare the total mass of the reactants to the total mass of the produc…
A. $30\ \text{g}\ \text{Li}_2\text{O} + 44\ \text{g}\ \text{CO}_2 ightarrow 74\ \text{g}\ \text{Li}_2\text{CO}_3$
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what mass of product is formed during the reaction in the graphic below…
$16.225\ \text{g}$
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compare the total mass of the reactants to the total mass of the produc…
A. $22\ \text{g}\text{Al} + 175\ \text{g}\text{Br}_2 ightarrow 197\ \text{g}\text{AlBr}_3$
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compare the total mass of the reactants to the total mass of the produc…
A. $12\ \text{g}\ \text{Cl}_2 + 13\ \text{g}\ \text{K} ightarrow 25\ \text{g}\ \text{KCl}$
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compare the total mass of the reactants to the total mass of the produc…
B. $102\ \text{g S} + 102\ \text{g O}_2 ightarrow 204\ \text{g SO}_2$
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based on the law of conservation of mass, what mass of product is forme…
55.12 g
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29/50 how many atoms are present if there is no subscript following the…
only 1
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how do the following two elements bond together? k⁺ s²⁻
$K_2S$ (the yellow-green bottom option)
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what element should always be in the center of a lewis dot structure? t…
The central atom should be the least electronegative element, or Carbon
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30 a piece of silver is measured to have a mass of 26.25 grams. its vol…
The density of the piece of silver is $10.5$ grams per cubic centimeter (or $10.5$ $g/cm^3$).
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28 all substances have the same melting point. true or false? propertie…
False
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23 is the ability to rust a physical or chemical property?
The ability to rust is a chemical property.
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part d: transition metals – thinking with roman numerals 7. write the s…
$\boldsymbol{Fe^{3+}}$ #### Copper (I)
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16/50 how many sodium atoms are in 6nacl?
6
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part b: electrons & charge reasoning 3. complete the table below. ion \…
### Question 3: Complete the table To complete the table, we use the atomic number (number of protons) and the charge to find the number of electrons. The net charge is calculated…
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part a: valence & ion prediction use the periodic table to answer the f…
### Question 1: Valence Electrons Calculation #### Step 1: Sodium (Na) - **Explanation**: Sodium is in Group 1 of the periodic table. For main - group elements, the number of vale…
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practice 14. complete the table. the first row is done for you. | ion n…
### Question 15 (Writing symbol and charge for transition metal ions) #### Step 1: Cobalt (II) The Roman numeral (II) indicates the charge is +2. The symbol for cobalt is Co. So t…
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which of the following is a compound? \\(\\ce{co2}\\) \\(\\ce{c}\\) \\(…
$\text{CO}_2$
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how do the following two elements bond together? al³⁺ o²⁻ options: alo,…
$\text{Al}_2\text{O}_3$ (the purple option)
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daoists seek harmony for confucius, the social order of family and gove…
4. The main beliefs of Daoists are: - A universal force called the Dao (the Way) guides all things. - People should seek order and live in harmony with nature, following the examp…
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when magnesium (mg) is bonding with oxygen (o), what kind of charge wil…
+2
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what is the lewis dot structure for a neutral atom of carbon (₆c)? the …
The element symbol C with 4 dots around it.
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what is the lewis dot structure for a neutral atom of sodium (₁₁na)? th…
The element symbol Na with 1 dot around it.
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what is the percent of oxygen by mass in a pure sample of fecr₂o₄? 1. 5…
5. 29%
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what is the volume of 1.56 kg of a compound whose molar mass is 81.86 g…
6. 37.9 mL
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calculate the number of carbon atoms in 0.75 l of acetone (ch₃coch₃). (…
4. \( 3.0 \times 10^{25} \) atoms
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how many moles of caco₃ would contain 14.5 g of oxygen atoms? 1. 0.302 …
2. 0.0716 mol
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6. molar mass 01 10 pts possible find the molar mass of pb(no₃)₂. answe…
331.22
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which of the following would contain the largest number of moles? 1. 5.…
5. 5.00 grams of lithium (Li)
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six moles of toluene are combined with two moles of benzene. what is th…
4. 0.25
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the total number of electrons in one mole of fluorine molecules (f₂) is…
4. \( 18 \times 6.0 \times 10^{23} \)
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u4g6 what is the molar mass of sodium? be sure to include units written…
22.99 g/mol (or 23.0 g/mol, depending on precision; the exact molar mass of sodium is approximately 22.99 g/mol)
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3. molar mass 10 pts possible find the molar mass of c₂h₅cooh. answer i…
$74.08$ (rounded to two decimal places, or $74.078$)
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anwar al - sadat and menachem begin won the nobel peace prize in 1978 f…
signing the Camp David Accords.
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2/50 which of the following is not an ionic compound: br₂ naoh cao bacl₂
$\text{Br}_2$
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is the molecule overall polar or nonpolar? options: nonpolar, polar
Polar
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is the molecule overall polar or nonpolar? polar nonpolar (with the mol…
Nonpolar
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3. compare the total number of valence electrons in each compound befor…
1. Ionic bonds form between metals and nonmetals; covalent bonds form between nonmetals (or metalloids and nonmetals). 2. Ionic bonds transfer valence electrons; covalent bonds sh…
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part 2: covalent bonding: follow the instructions and record your data …
1. Valence electrons are shared: some form shared bonded pairs between atoms, while others stay as unshared lone pairs on each atom, to fill each atom's valence shell for stabilit…
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question 5 how is molecular formula related to empirical formula? one v…
It can be equal but it is usually a simple integer multiple of the empirical formula ### Question 6
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question 3 1 pts how is an empirical formula calculation related to a p…
B. They are exactly the reverse of each other in terms of math steps ### Question 4
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question 1 1 pts what is the ratio of atoms in the compound hcl? 1 to 3…
1 to 1 ### Question 2
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which describes a climate effect on the rate of weathering? ○ cold clim…
A. Cold climates favor mechanical weathering.
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organic material provides nitrogen for plants. which soil component con…
B. humus
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question 7 diatomic elements are important. what makes them different f…
B. The atoms are found in pairs in nature. ### Question 8
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if there are $12 \\times 10^{23}$ oxygens in a sample of water, how man…
s: First Question (Hydrogen in water):
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5 zinc reacts with copper(ii) chloride to give copper metal and a solut…
### Question 5: $\boldsymbol{\text{Zn (s)}} + \boldsymbol{\text{CuCl}_2 \text{ (aq)}} ightarrow \boldsymbol{\text{Cu (s)}} + \boldsymbol{\text{ZnCl}_2 \text{ (aq)}}$ ### Question …