化学
化学反応、化学量論、分子構造、元素の性質。
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ammonia, nh₃, is a common chemical compound used in cleaning products a…
The correct statement is "Three molecules of ammonia would contain 3 atoms of nitrogen and 9 atoms of hydrogen" (the last option among the given choices).
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2. what is the volume of water occupied by 100.0 g of water? remember t…
The volume of water is $100.0\space cm^3$ (or $100.0\space mL$ since $1\space cm^3 = 1\space mL$).
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the chemical formula for a molecule of acetaminophen is displayed below…
There are 20 total atoms involved in the chemical formula for a molecule of acetaminophen.
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2 which of the following lists all the elements that are present in a m…
The elements present in a molecule of calcium phosphate \( \text{Ca}_3(\text{PO}_4)_2 \) are Calcium, Phosphorus, and Oxygen. So we check the boxes for Calcium, Phosphorus, and Ox…
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abby added baking soda and vinegar to a flask. she stretched a balloon …
The mass should be the same since matter is conserved in a chemical reaction (the gas produced is trapped in the balloon, so total mass of the system remains unchanged). (The opti…
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element name | isotopic symbol | atomic number | mass number | # of pro…
To solve the missing values in the table, we use the following relationships: - Atomic Number = Number of Protons = Number of Electrons (in a neutral atom). - Mass Number = Number…
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value: 3 a ___ reaction is a process that occurs when two or more molec…
a. chemical
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name _______________ class _______________ date _______________ reinfor…
If the red chemical is in a liquid layer at the bottom (or a lower layer) of the tank, open the tap at the bottom of the tank to drain the liquid layer that contains the red chemi…
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value: 3 ____ reactions are processes in which one or more nuclides are…
b. Nuclear
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match the terms to their definition. 1. distress 2. endorphins 3. envir…
1. distress - Bad stress that creates sadness and anxiety 2. endorphins - chemicals released by the body that relieve mild depression and provide you with a feeling of peace and h…
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reinforcement continued class date 4. use colored pencils to sketch and…
If the red chemical is in a lower - density layer, we can carefully pour off the upper layers. If it is in a higher - density (lower) layer, we can open the tap at the bottom of t…
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value: 3 stable atoms have ____ energy states. ○ a. higher ○ b. lower #…
b. lower
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name semina dack date 9/10/25 scientific method read & write handout te…
Laura accidentally got black permanent marker on her new, white shirt. ### Question 2
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which of the following best describes anabolic steroids? ○ anabolic ste…
Anabolic steroids are hormone - like substances that are synthetic.
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a matter of density imagine that you work at a chemical plant. this mor…
s: ### 1. Densities: - Green liquid: $\boldsymbol{0.75}$ kg/L - Blue liquid: $\boldsymbol{0.9}$ kg/L - Red liquid: $\boldsymbol{1.2}$ kg/L - Black liquid: $\boldsymbol{0.8}$ kg/L …
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two iron rods are placed horizontally, touching end-to-end. one end of …
D. The molecular movement in the first rod transferred energy to the molecules in the second.
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match the terms to their definition. 1. club drugs 2. drug abuse 3. inh…
1. club drugs - ecstasy (MDMA), Gamma - hydroxybutyrate (GHB), Rohypnol (roofies), Ketamine (K) 2. drug abuse - Compulsive use or overuse of drugs 3. inhalants - any one of about …
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which of the following medications requires special disposal because it…
A. A partially used vial of chemotherapy medication
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a cold cast iron skillet is placed onto a stove top. when the stove is …
C. The skillet is gaining energy (heat) from the stove.
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a student conducts an experiment to test how the temperature affects th…
B. the temperature of the water
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vocabulary for each pair of vocabulary words, write one sentence that d…
The four characteristics of a state are: 1. Population (people living within it); 2. Territory (defined geographic area with boundaries); 3. Sovereignty (supreme authority within …
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tai chi is a good example of an activity that improves: a. energy level…
d. Balance ### Second Question:
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question 1 (4 points) saved which one of the following sets of quantum …
\(n = 4, l = 2, m_l=-1, m_s = - 1/2\) (the third option: \(n = 4, l = 2, m_l=-1, m_s=-1/2\))
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practice table - valence electrons & atoms vs. ions fill in the chart b…
To solve the table, we use the following concepts: - Atomic number ($Z$) = number of protons ($p^+$) = number of electrons ($e^-$) in a neutral atom. - For ions: Charge = $p^+ - e…
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practice table - valence electrons & atoms vs. ions fill in the chart b…
To solve the table, we use the following concepts: - Atomic number (\(Z\)) = number of protons (\(p^+\)) = number of electrons (\(e^-\)) in a neutral atom. - Charge = \(p^+ - e^-\…
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value: 3 when water turns into ice, its molecules ____. ○ a. expand ○ b…
a. expand
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value: 3 if 100g of ice is melted, 100g of water are formed. this 100g …
c. conservation of mass
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exercise impacts mental health by improving levels of which two neurotr…
b. Dopamine and serotonin ### Second Question:
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quiz 6.2.1 - energy forms value: 16 match the description to the energy…
1. Elastic energy - e 2. Thermal energy - a 3. Gravitational energy - d 4. Nuclear energy - b 5. Electrical energy - c
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question 2 (1 point) saved what is obscured 2.00)/(1.2465 + 3.45) writt…
e) 62.8
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multiple-choice question the image below tells us that fluorine should …
7. The option corresponding to 7 (the checkbox next to 7) should be selected.
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the image below tells us that magnesium should be in group ____. (remem…
2 (the option with "2")
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which of the following is the number of grams of dextrose in 500 ml of …
50 g (corresponding to the option with 50 g)
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what is an example of a cost - saving strategy for eating healthy? a. b…
a. Buying frozen fruits and vegetables ### Second Question: What function does protein serve in the body?
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multiple-choice question by looking at the bohr models for the elements…
6 (assuming the Bohr models show elements with 6 valence electrons, which corresponds to group 6 in the periodic table)
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the first real model of the atom was proposed in 1803. it described the…
The correct option is: Experiments on the atom provided new evidence that changed the model. (The option with the text "Experiments on the atom provided new evidence that changed …
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homework- protons, neutrons, elements pra... / king foster - subatomic …
To solve for the missing values (Protons, Neutrons, Electrons) in the table, we use the following relationships: - **Protons = Atomic Number** (by definition of atomic number). - …
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complete the rhyme scheme. all nature seems at work. slugs leave their …
Line 1: A Line 2: B Line 3: A Line 4: B Line 5: C Line 6: C
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match the terms to their definition. 1. micronutrients 2. minerals 3. n…
1. micronutrients - nutrients that are needed by the human body, but only in small amounts 2. minerals - inorganic substances that are needed in minimal amounts to regulate, grow,…
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errors in measurement (see table t): percent error is a way for scienti…
The percent error is approximately \(-8.46\%\) (or \(-8.4\%\) if rounded to one decimal place, or as calculated more precisely \(-8.4133\%\) from the handwritten note).
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value: 5 factors that affect the rate of reaction include ______, _____…
a. an increased concentration of reactants, b. An increase in temperature, c. an increase in light, d. an increase in pressure
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complete the rhyme scheme. the sun was shining on the sea, shining with…
The rhyme scheme is A, B, C, B, D, B.
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value: 3 the rate of chemical reaction is the ___ at which reactants ar…
b. speed
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value: 3 an increase in temperature _____ the rate of a reaction. a. de…
b. increases
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value: 3 the rusting of iron is an example of ___ chemical reaction. a.…
a. slow
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question 2 (1 point) what is 56 + (32.00)/(1.2465 + 3.45) written with …
# Explanation: ## Step1: Calculate the denominator First, we calculate the sum in the denominator: \(1.2465 + 3.45\). When adding, we consider the number of decimal places. \(1.24…
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value: 3 the more likely two molecules are to collide every second, the…
a. faster
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value: 4 in endothermic reactions, heat ______ as a reactant in the che…
b. is absorbed
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value: 8 match the description to the terms. a. refers to reactions tha…
a. 3. Endothermic b. 1. Enthalpy c. 2. Exothermic
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value: 4 ____ is signified by the letter h. a. enthalpy b. exothermic c…
a. Enthalpy
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dynamic chemical equilibrium occurs when the rate of a chemical reactio…
b. the same
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le chatelier’s principle can be used to predict the behavior of a syste…
a. Pressure, b. Temperature, c. Concentration
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15. for each substance listed in the table below identify if the molecu…
To solve this, we recall: An **element** is a pure substance made of only one type of atom. A **compound** is a pure substance made of two or more different types of atoms (elemen…
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value: 3 when the concentration of a reactant is ___, the chemical equi…
b. increased
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investigation #1: what happens when you add a mentos to a bottle of die…
Type: descriptive Limitation: variables not controlled (or interferes with environment) ### Investigation #2:
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the letter __ is a symbol for the equilibrium constant. a. k b. l c. p …
a. K
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fill in the name and empirical formula of each ionic compound that coul…
### For $\boldsymbol{\ce{Zn^{2+}}}$ and $\boldsymbol{\ce{OH^-}}$: ## Step1: Balance charges The cation is $\ce{Zn^{2+}}$ (charge +2) and the anion is $\ce{OH^-}$ (charge -1). To b…
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investigation #1: what happens when you add a mentos to a bottle of die…
Type: descriptive Limitation: variables not controlled ### Investigation #2
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value: 4 ____ reactions are also known as replacement reactions. a. oxi…
d. Displacement
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practice it! sally is a chemist who read an article about how 40% of th…
comparative
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value: 3 identify the strong acid. a. hydrochloric acid b. milk of magn…
a. Hydrochloric acid
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name of element | element symbol | mass number | atomic number | proton…
To solve for the missing values in the table, we use the following relationships in atomic structure: - **Atomic Number (Z)** = Number of Protons = Number of Electrons (in a neutr…
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value: 4 _____, or combination reactions, are the opposite of decomposi…
b. Synthesis
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value: 3 a ___ reaction occurs when the reactant(s) combine with oxygen…
c. combustion
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value: 3 identify the example of a decomposition reaction ○ a. sodium (…
c. 2 hydrogen peroxide molecules (H₂O₂) are broken down into 2 water (H₂O) and 1 oxygen molecule.
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select the text from the paragraph that best helps you understand that …
Proponents of DDT usage pointed to the pesticide as a cost - effective means of controlling mosquito populations in parts of the world with high malaria rates.
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however, pushed back against carsons claims. proponents of ddt usage po…
people who argue for the value of something
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h h number atoms 2 elements 1 compounds 2 if the classification is
The error is in the "Compounds" row; the correct number of compounds is \(0\) (since \(H_2\) is an element, not a compound).
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match each experiment to the subatomic particle it helped discover. sub…
Electron - Cathode ray tube experiment Proton - Gold foil experiment Neutron - Beryllium sheet experiment
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14. diagram: nitrogen (n) atom at center, four hydrogen (h) atoms aroun…
| | Number | |----------|--------| | Atoms | 5 | | Elements | 2 | | Compounds| 1 | (For the "Elements" row, the answer is 2; for "Compounds" row, the answer is 1. If you need indi…
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atoms elements compounds number compounds per ble below vol
The total number of atoms in the given molecule (as per the diagram) is \( \boldsymbol{5} \) (1 nitrogen atom and 4 hydrogen atoms).
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number, atoms, elements, compounds (with handwritten numbers 4, 2, 1) a…
To determine the components and atoms in the compound (let's assume the compound is \( K_2CO_3 \) from the diagram with \( K \), \( C \), \( O \) atoms): ### Step 1: Identify Elem…
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13. diagram of na and cl (two circles, one labeled na, one cl) table wi…
| | Number | |----------|--------| | Atoms | 2 | | Elements | 2 | | Compounds| 1 |
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which of the following is an example of peer norms? a. everyone is usin…
b. Most teens choose to stay drug - free ### Second Question (Marijuana Psychoactive Chemical)
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for each row in the table below, decide whether the pair of elements wi…
compound formed: neither; chemical formula: (no compound) ### Row 2:
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value: 6 match the description with the chemical reaction type. a. this…
a. 1. Acid - base b. 3. Synthesis c. 4. Decomposition d. 2. Precipitation
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complete the rhyme scheme. across the sky a lowly sigh from west to eas…
For the second line ( "From west to east the sweet wind carried" ), the rhyme scheme letter is $\boldsymbol{b}$ (and following the pattern, the subsequent lines have rhyme schemes…
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value: 3 a ____ is said to have occurred when bonds between atoms are f…
a. chemical reaction
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for each row in the table below, decide whether the pair of elements wi…
| element #1 | element #2 | compound formed? | chemical formula | | ---- | ---- | ---- | ---- | | carbon | chlorine | molecular | $CCl_4$ | | sodium | lithium | neither | - | | su…
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which of the following rules is true about balancing chemical equations…
a. You can change the coefficient(s) of the chemicals involved. b. You cannot change the subscript(s) of the chemicals involved.
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value: 4 identify the products in the chemical reaction of vinegar and …
a. \( \text{NaC}_2\text{H}_3\text{O}_2 \), c. \( \text{H}_2\text{O} \), e. \( \text{CO}_2 \)
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value: 4 which of the following part of the chemical formula represents…
c. Symbol
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value: 4 which of the following represents the number of the molecules,…
a. Coefficient
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value: 4 which of the following formulas has one carbon atom and four h…
d. $\ce{CH4}$ (Methane)
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value: 4 which of the following parts in the chemical formula represent…
b. Reactant
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value: 3 bases or alkaline are known to ______ protons. a. accept b. do…
a. accept
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value: 4 match the acidity and alkalinity to the ph level. a. sour tast…
1. Acid property: a. Sour tasting 2. Alkaline property: b. Bitter
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value: 3 acids are known to ______ protons. a. accept b. donate # 3/5 <…
b. donate
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solutions with a ___ concentration of hydrogen ions have a low ph. a. h…
a. high
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value: 4 match the acidity and alkalinity to the ph level. a. a solutio…
1. Neutral: c. A solution with a pH of 7. 2. Acidic: b. A solution with a pH below 7. 3. Alkaline/Base: a. A solution with a pH above 7.
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value: 3 electronegativity refers to how well an element ______ electro…
a. attracts, d. hold onto
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value: 5 match the type of bond with the correct difference in electron…
1. Non - polar - covalent bond: a. Electronegativity difference is between 0 - 0.4 2. Polar - covalent bond: c. Electronegativity difference is between 0.5 - 1.7 3. Ionic bond: b.…
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value: 3 the trend for electronegativity on the periodic table is that …
c. left to right, d. bottom to top
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which of the following elements has no electronegativity, and is inert …
a. Neon, b. Argon, c. Helium
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value: 3 the ___ rule refers to the tendency of most atoms to prefer to…
octet
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one of the main properties of covalent bonds is that they form ____ bon…
b. strong
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____ covalent bonds occur when atoms share a pair of electrons in a cov…
b. Nonpolar
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value: 3 when two atoms, with incomplete valence shells, share electron…
a. covalent
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value: 5 match the number of electrons shared in covalent bonds to the …
1. Single covalent bond: b. Two shared electrons 2. Double covalent bond: c. Four shared electrons 3. Triple covalent bond: a. Six shared electrons
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value: 3 in the case of ___ covalent bonds, the electron pair in a bond…
a. polar