化學
化學反應、化學計量、分子結構與元素性質。
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chemicals in tobacco products quick check how does nicotine affect the …
increases heart rate
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chemicals in tobacco products quick check a person who hasnt smoked for…
withdrawal
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chemicals in tobacco products quick check the addictive chemical found …
nicotine.
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3. why is sodium ion chosen as the cation of all three solutions that w…
Sodium ion is chosen as the cation for ion - identification solutions mainly because: 1. Most sodium salts are soluble in water, so \(Na^+\) will not form a precipitate with the a…
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4. find the mass of iron (ii) sulphate needed to prepare 250ml of 0.600…
s: 4. The mass of iron (II) sulphate is \( \boldsymbol{24.33\ \text{g}} \) (using \( M = 162.2\ \text{g/mol} \)) or \( \boldsymbol{22.8\ \text{g}} \) (using anhydrous \( \text{FeS…
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volatile organic compounds (vocs): the most ______ of indoor air pollut…
1. common 2. paints, cleaning supplies, pesticides (or other relevant products) 3. so many different VOCs 4. formaldehyde
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12. $\\ce{cu + agno_{3}}$ $\\ce{ag + cu(no_{3})_{2}}$ answer: 13. $\\ce…
12. $\text{Cu} + 2\text{AgNO}_3 ightarrow 2\text{Ag} + \text{Cu(NO}_3\text{)}_2$ 13. $\text{Pb(NO}_3\text{)}_2 + 2\text{KI} ightarrow \text{PbI}_2 + 2\text{KNO}_3$ 14. $\text{HCl}…
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2. how do solubility rules help predict which reactions will produce a …
Solubility rules help in predicting precipitation reactions as follows: 1. For a reaction (usually double - displacement) involving ionic compounds, determine the possible product…
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sources of outdoor chemical hazards - in the air: ____________, such as…
- In the air: natural sources - In the ground: industrial waste (or oil leaks, based on the image) - In the water: runoff - Bioaccumulation: accumulation of a substance in an orga…
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covalent bond formation depends on the ability of atoms to donate elect…
D. share electrons with other atoms (assuming the options are labeled A - E with D being "share electrons with other atoms")
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question 1 of 5 which of these compounds can be expected to have the lo…
\( \boldsymbol{\text{C}_6\text{H}_{12}} \) (the option with \( \text{C}_6\text{H}_{12} \))
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learning goals - understand the properties of cations (positive ions) a…
1. A chemical reaction where two soluble ionic solutions are mixed, and their ions recombine to form an insoluble solid (precipitate) that separates from the liquid mixture. 2. So…
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instructions balance each chemical equation below. students may work fo…
1. $2\text{H}_2 + \text{O}_2 ightarrow 2\text{H}_2\text{O}$ 2. $\text{N}_2 + 3\text{H}_2 ightarrow 2\text{NH}_3$ 3. $\text{C} + \text{O}_2 ightarrow \text{CO}_2$ 4. $4\text{Fe} + …
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lewis structure for covalent compounds (remember octet 8) practice prob…
### Problem 1: \( \boldsymbol{F_2} \) #### Step 1: Determine Valence Electrons for Fluorine Fluorine (F) is in group 17, so it has 7 valence electrons. Since there are two F atoms…
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2) read the following graduated cylinders in milliliters. be specific! …
68 #### b.
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which element is an example of a metalloid? a gold b helium c d
D. silicon
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atom a has an atomic number of 19 and a mass number of 40. atom b has a…
B. Atom A has one less proton and one more neutron than Atom B.
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helium, neon, and argon are examples of a metals. b metalloids. c noble…
C. noble gases.
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the periodic table organizes elements according to increasing a atomic …
C. atomic number.
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the elements from this section of the periodic table all belong to the …
C. period.
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which word or group of words is represented by the word \period\ in the…
C. Energy Level
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which best describes the location of non - metals on the periodic table…
D. upper right corner
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using the periodic table and your knowledge of atomic structure. cobalt…
B. Cobalt has one less proton.
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place each statement in the column of the particle that it best describ…
**Protons** - positive charge found in the nucleus - periodic table is set up based on the number of these - gives the identity of the atom **Neutrons** - neutral charge and helps…
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the atomic number is considered a unique atom and element identifier. d…
B. The proton number remains constant through changing the atomic charge, energy, and isotopes.
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22. what evidence best supports the presence of atmospheric oxygen 2.7 …
A. layered iron rust in rocks
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when the elements copper (cu) and oxygen (o) chemically combine, they f…
a compound
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this image is a model of... a homogenous mixture a heterogeneous mixtur…
D. an element (assuming the green option is labeled D, if the labels were A: a homogeneous mixture, B: a heterogeneous mixture, C: a compound, D: an element)
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which of the following is an example of the formation of a mixture? rus…
The option with "Sugar crystals dissolving in water" (the blue - colored option with the text "Sugar crystals dissolving in water")
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question 4 (1 point) if a cosmetologist observes that a clients face ha…
c. triangular ### Question 5
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the image below is an example of a molecule an atom a homogeneous mixtu…
a homogeneous mixture
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which of the following explains why saltwater is considered a mixture? …
The option with the text "It is composed of two or more substances and retains their own chemical properties." (the yellow - colored box)
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which of the following is an example of a container filled with a pure …
A. A balloon filled with helium.
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the image below is an example of a homogeneous mixture an element a het…
a heterogeneous mixture
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which statement identifies why oxygen is classified as a pure substance…
The correct statement is the green - colored one: "Oxygen contains only one substance, but air contains several substances." (Assuming the green option is, for example, Option A, …
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three students are working with different substances to measure the che…
Chao should change the temperature, Mia should adjust the pressure, and Ezra should increase the surface area.
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when the elements copper (cu) and oxygen (o) chemically combine, they f…
a compound
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this picture is a model of a... element compound heterogeneous mixture …
heterogeneous mixture (the orange card option: heterogeneous mixture)
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the chemical equation shown below represents a reaction that produces f…
The substance classified as an element is \( \text{H}_2 \) (Hydrogen gas). If we consider the options as presented (assuming the choices are \( \text{CO}_2 \), \( \text{H}_2 \), \…
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when electricity passes through water, hydrogen and oxygen are produced…
The green - colored option (Water-- > Compound, Hydrogen-- > Element, Oxygen-- > Element)
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the chemical symbol for an element is always represented by only 1 lett…
False
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valence electrons are the electrons in the outer most energy level all …
the electrons in the outer most energy level
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the number of valence electrons ------- by 1 as you move across the per…
increases
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atomic mass equals the combined number of protons and electrons electro…
Protons and Neutrons (the orange - colored option with text "Protons and Neutrons")
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what is a motion in limine? a. a motion to dismiss the case b. the move…
c. A pretrial motion for the purpose of excluding certain evidence
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e) 9.0h + hbr3 9. mark and karen are carrying out a science project on …
When acid is added, $\ce{HCO3^-}$ reacts with added $\ce{H+}$ to form $\ce{H2CO3}$, preventing a large pH drop. The buffer equilibrium shifts left to consume excess $\ce{H+}$. ###…
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investigating chemical reactions: energy changes in substances when dif…
chemical reaction ### Question 2
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practice problems 1 the height of water in a bathtub, w, is a function …
A - 2, B - 4, C - 3, D - 1 ### Problem 2a
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akia is balancing the equation na + h₂o → naoh + h₂. he tries to find t…
by counting each individual atom and making sure the number of each kind of atom is the same in the reactants and the products
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which statement correctly describes why a compound is a pure substance?…
A compound is a pure substance because its molecule cannot be broken down into simpler particles by physical means.
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select the correct answer. which of the following is a correctly balanc…
B. $2\text{HgO} ightarrow 2\text{Hg} + \text{O}_2$
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write the correct chemical formula of polyatomic compounds covalent com…
### Part 1: Naming Covalent Compounds (Question 1) For covalent compounds, we use prefixes to indicate the number of atoms of each element. The prefixes are: 1 - mono, 2 - di, 3 -…
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part ii: lab questions 1. graph the following data on a piece of graph …
The graph is drawn by following the above steps, with properly labeled axes, appropriate scales, and two solubility curves (one for Sodium Chloride and one for Copper Sulfate) dra…
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research: real world examples research 3 examples of each change in sta…
To complete this task, we will provide 3 examples for each state change (melting, freezing, condensation, sublimation) and their explanations: ### MELTING 1. **Example 1: Candle W…
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changes in state: vocabulary matching match the word to the definition …
- GASES: No definite volume and no definite shape. - TEMPERATURE: The average kinetic energy of particles in a substance. - KINETIC ENERGY: Energy of motion. - VAPORIZATION: Liqui…
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7. elements review: fill in the chart below for some of the compounds o…
To solve this, we analyze each compound: ### Example: NaCl ## Step 1: Count Na atoms In \( \text{NaCl} \), there is 1 Na atom. ## Step 2: Count Cl atoms In \( \text{NaCl} \), ther…
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at 90°c, you dissolved 10 g of kcl in 100. g of water. is this solution…
To solve these problems, we typically refer to a solubility curve (a graph showing the solubility of various compounds in water at different temperatures). Since the specific solu…
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2) types of solutions on a solubility curve, the lines indicate the con…
First blank: saturated Second blank: below
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from nature, addresses, and lectures 1. the first in time and the first…
4. Man desires to find the interrelation of elements in nature.
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8. the most useful property of metalloids is their a. varying ability t…
a. Varying ability to conduct electric current ### Question 9
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final for semester 1 name online portion (____ / 93 pts) + paper portio…
### Part 1: Molar Mass Calculation #### For $\boldsymbol{Fe_2(SO_4)_3}$ - Atomic masses: $Fe = 55.85\ \text{g/mol}$, $S = 32.07\ \text{g/mol}$, $O = 16.00\ \text{g/mol}$ - Molar m…
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determine the percentage composition of hydrogen (h) in hcl find total …
The percentage composition of hydrogen (H) in HCl is approximately 2.76%.
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multiple choice question misty begins her conclusion by saying, \my pur…
D. She starts off with the phrase "my purpose today has been."
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antonio stradivari and other craftspeople in the sixteenth to eighteent…
I quality of Cremonese violins results in part from a method the craftspeople used to alter the wood
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tobacco teaser 1. cigarette smoking is the most? cause of death in amer…
1. L. preventable 2. I. nicotine 3. C. inhale 4. A. wrinkles 5. G. cigars 6. K. addicted 7. F. carbon monoxide 8. H. eighteen 9. N. lung cancer 10. D. tar 11. M. lungs 12. E. with…
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1. using the formula given below, determine whether the ions will attra…
### Table for Step1 (already provided, confirmed): | Variable | Charge | Equation Value | |----------|--------|----------------| | $q_1$ | $+3$ | $3$ | | $q_2$ | $-2$ | $2$ | ### …
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multiple choice question if your specific purpose is \to persuade my au…
C. a reason why listeners should only eat organic produce
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name: ice cream in a bag chemistry plays an important role in many ever…
1. An ion is an atom with a charge. 2. A phase change is when matter goes from one state to another as a result of an energy exchange. 3. When salt is added to ice, the salt disso…
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name: myles date: jan 13th block: 2nd 1. for each of the following, lab…
nonmetal #### b.
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directions: two beakers of water are heated on the same stove for exact…
Beaker A will have a higher temperature because the same amount of energy was added to a smaller mass.
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na₂co₃ + pb(no₃)₂ → pbco₃ + 2nano₃ 25.1 g of sodium carbonate reacts wi…
\( 63.3 \)
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what is the overall energy transformation in a coal - fired power plant…
chemical to electrical
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the formation of photochemical smog is a result of a series of reaction…
A. evaporation from gasoline
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a) 1s²2s²2p⁶3s³3d⁵ -
# Explicación: ## Paso 1: Recordar reglas de orbitales Los orbitales $s$ admiten máximo 2 electrones. ## Paso 2: Identificar error en el orbital El término $3s^3$ es inválido, ya …
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pebworth, logan sps_physical science_checkpoint2_2025-2026 23 of 40 pla…
1, 3, 2 (in order for $\text{C}_2\text{H}_4$, $\text{O}_2$, $\text{CO}_2$)
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directions: why does neon (group 18) rarely form compounds with other e…
C. It is already chemically stable because its outer energy level is full.
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directions: select the equations that correctly demonstrate the law of …
$2H_2 + O_2 \to 2H_2O$ $C + O_2 \to CO_2$
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directions: an unknown element from group 1 reacts with an element from…
B. An ionic bond is formed because the metal loses an electron to the nonmetal.
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directions: look at the formula for glucose: $c_6h_{12}o_6$ which of th…
- There are a total of 24 atoms in one molecule of glucose. - There are exactly 12 hydrogen atoms in the molecule. - The ratio of Carbon to Oxygen atoms is 1:1.
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7. which of the following is true about isotopes? a) they have differen…
c) They have different numbers of neutrons. ### Question 8
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1. which of the following is a characteristic of an ion? a) it has no c…
B. It has either a positive or negative charge. ### Question 2
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the table lists two experiments performed using aluminum foil. | experi…
Experiment 1 shows a physical change because the aluminum curls up due to heat. Experiment 2 shows a chemical change because a new substance forms on the aluminum.
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mixing baking soda and vinegar makes the temperature of the solution de…
New elements were formed.
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pebworth, logan sps physical science checkpoint2 2025 - 2026 directions…
B. Electrostatic forces between positive and negative charges
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pebworth, logan sps_physical science_checkpoint2_2025-2026 question: a …
An element located on the far left side.
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multiple-choice question what is compost? water and soil used to help f…
B. Mixture of organic matter mixed with earth materials like dirt or woodchips.
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the empirical formula of hydroquinone is shown below. the molar mass of…
2. \( C_6H_6O_2 \)
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1. to avoid a possible burn when opening the oven, you should stand: a.…
1. A. TO THE SIDE OF THE OVEN. 10. B. A SHARP KNIFE 11. A. WIPE IT UP IMMEDIATELY. 12. C. WITH THE SIDE OF THE LID AWAY FROM YOU. 13. C. KEEP KNIVES SHARP AND USE THE APPROPRIATE …
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after six years of successional time, about how much organic mass is pr…
410 g/m^2/yr
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1. atomic structure | description | atomic number | mass number | net c…
# Explanation: --- ### Parte 1: Estructura Atómica ## Paso 1: Calcular número atómico El número atómico es igual al número de protones ($p^+$). ## Paso 2: Calcular número de masa …
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applying theory to practice 1. when we say an ion has a positive charge…
1. A positive ion has more protons than electrons, having lost one or more electrons. 2. For ions, "opposites attract" means positively charged ions (cations) are attracted to neg…
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question 2. classify the reaction in each of the following equations: a…
a) Double-displacement reaction b) Synthesis reaction c) Combustion reaction d) Decomposition reaction e) Single-displacement reaction
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in 1899, swedish chemist svante arrhenius developed an equation to answ…
A. remains
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practice: isotope calculations #2 1. complete the following table. | is…
### Part 1: Completing the Table To complete the table, we use the following relationships: - **Atomic Number (\(Z\))** = Number of Protons = Number of Electrons (in neutral atoms…
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15. how many grams are equal to 0.11 mole of copper(i) chromate, $\\ce{…
27 grams (or 26.74 grams for more precision)
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periodic table name: jaydin milladate: section 1 use the following clue…
1. Atomic number: 9; 2. Mass number: 19; 3. Valence electrons: 7; 4. Period: 2; 5. Electron configuration: 2,7; 6. Classification: non - metal; 7. Name: Fluorine; 8. Symbol: F ###…
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quiz instructions question 7 4 pts find the pairs: organic no more than…
- organic: no more than 5% of the food is produced without the use of chemical fertilizers, pesticides or other artificial agents - fat - free: must have 0.5 grams or less of fat …
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quiz instructions question 7 4 pts find the pairs: organic no more than…
- organic: no more than 5% of the food is produced without the use of chemical fertilizers, pesticides or other artificial agents - fat - free: must have 0.5 grams or less of fat …
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quiz instructions question 7 4 pts find the pairs: organic: no more tha…
To solve this matching problem, we analyze each term and its corresponding definition: ### 1. Organic The definition for "organic" relates to food production without synthetic inp…
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quiz instructions question 7 4 pts find the pairs: organic no more than…
must have 0.5 grams or less of fat per serving