化學
化學反應、化學計量、分子結構與元素性質。
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the smallest unit of matter is a(n) ______. choose one option a molecul…
B. atom
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i can’t list every blank on the periodic table, but i know a few, like …
element
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drag the right word to its synonyms bond electron stick, cohere periodi…
Drag "bond" to the blue circle with "stick, cohere".
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the difference between a physical change and a chemical change is that …
B. boiling water, C. breaking ice, D. carving a wooden statue
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fill in the word that correctly completes this sentence. a pure substan…
mixture
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drag the right word to its definition the smallest particle of an eleme…
The word "atom" should be dragged to the definition "the smallest particle of an element that can exist".
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drag over the word that goes best with the image
element
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what is the word used to describe anything that has mass and takes up s…
D. matter
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drag the right word to its definition the physical substance that every…
The word that matches the definition "the physical substance that everything is made of" is "matter". So we drag "matter" to the definition.
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an atom of carbon will with an atom of oxygen to form the molecule carb…
bond
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drag the missing word into place so, dmitri mendeleev lined us elements…
periodic table
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drag the missing word into place my teacher said is anything that takes…
matter
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drag the missing word into place let me tell you something you might no…
The missing word is "atom", so we drag "atom" into the blank. The correct option is the one with "atom".
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drag the right word to its definition a table that shows all the elemen…
The word that matches the definition "a table that shows all the elements arranged by atomic number" is "periodic table". So we drag "periodic table" to the definition.
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drag the missing word into place a(n) of carbon dioxide contains one ca…
molecule
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4. specific gravity. the specific gravity (sg) of a mineral is the rati…
Based on observation, **A) Galena** likely has the highest specific gravity. Lead (Pb) is a very dense element, so Galena’s composition (PbS) suggests it will be heavier than the …
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5. write the net ionic equation for the neutralization of the bases, ma…
For $\ce{Mg(OH)2}$: $\boldsymbol{\ce{Mg(OH)2(s) + 2H+(aq) -> Mg^2+(aq) + 2H2O(l)}}$ For $\ce{Al(OH)3}$: $\boldsymbol{\ce{Al(OH)3(s) + 3H+(aq) -> Al^3+(aq) + 3H2O(l)}}$
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woodworking technology safety test answers use only these words to fill…
To solve this fill - in - the - blank safety test for woodworking technology, we analyze each question based on woodworking safety knowledge: ### Question 1 In case you are injure…
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use the references to access important values if needed for this questi…
1 ### Second Sub - Question: Subtraction of 20.90 from 41.1
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no additional details were added for this assignment. weathering breaks…
barrier islands
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week 1 ssa penda homework - sc.6.e.6.1 (weathering, erosion, deposition…
First blank: creates Second blank: moves Third blank: builds up
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select the statement(s) that best describe what happens during physical…
- Chemical weathering is the breakdown of rock by chemical processes. - Chemical weathering is when the rocks or minerals react chemically with air or water to form new substances…
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question 7 of 10 which description is an example of direct characteriza…
B. Steve was the strongest wrestler on the team, yet he was several inches shorter than his opponents.
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question 11 1 pts when a base is added to water, the ph should ______. …
B. increase ### Question 12
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question 13 1 pts which of the following statements is true? acids and …
A. Acids and bases will neutralize each other.
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10 multiple choice 1 point where are the lowest energy electrons locate…
Innermost shell
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9 multiple choice 1 point electrons travel around the nucleus of the at…
C. shells or orbitals
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question 4 (1 point) 0.00028 g = ________ mg blank 1: |
\(0.28\)
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question 2 (1 point) 39 g = ____ mg blank 1: | next page back
\(39000\)
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which of the following are considered subatomic particles? neutrons ele…
- neutrons (checked) - electrons (checked) - protons (checked) - Ions (un - checked)
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question 1 (1 point) 15.8 g = ______ dg
158
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what do atoms make up? ○ periodic table ○ only solid matter ○ chemical …
D. everything (assuming the last option is labeled D; if the options are labeled A - D as A. periodic table, B. only solid matter, C. chemical reactions, D. everything, then the a…
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which of the following best describes a chemical reaction? a) atoms rea…
A) Atoms rearrange to form new substances
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which part of an atom carries a positive charge? electron proton neutro…
B. Proton
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which of the following is true about ionic bonds? ○ they are the weakes…
B. Electrons are transferred from one atom to another
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what is an atom? ○ a mixture of elements ○ the smallest unit of an elem…
B. The smallest unit of an element that retains its properties
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which of the following is a molecule? ○ oxygen gas (o₂) ○ neon (ne) ○ i…
A. Oxygen gas ($O_2$)
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which of the following is not a functional group that can bond with car…
All of these functional groups can bind with carbon.
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in a chemical reaction, which aspect of the reactants changes? (1 point…
A. arrangement of the atoms
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4. 100.0 g of 4.0°c water is heated until its temperature is 37°c. calc…
The heat energy needed is approximately \( 1.4 \times 10^4 \, \text{J} \) (or 13794 J, or 13.8 kJ).
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matter conservations matters quick check which change is chemical? (1 p…
B. water undergoing electrolysis: liquid water becoming oxygen and hydrogen molecules (assuming the options are labeled A, B, C, D with this as one of them; if original labels dif…
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in the following diagram, what does the number 12 represent? diagram: 6…
An atomic mass
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although all are true, what is the best conclusion from the fact that e…
B. Atoms are comprised mostly of empty space.
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how are molecules different from atoms? they consist of several atoms b…
A. They consist of several atoms bonded together.
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the word \atom\ comes from a greek word for \indivisible.\ in what way …
B. They cannot be broken apart without losing their chemical properties.
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which of the following is not a functional group that can bond with car…
All of these functional groups can bind with carbon.
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complete the activity to practice what you have learned. which statemen…
The number of carbon atoms in the reactants and products are equal.
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question 13 1 pts which of the following statements is true? ○ acids an…
A. Acids and bases will neutralize each other. ### Question 14
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question 11 1 pts when a base is added to water, the ph should ______. …
B. increase ### Question 12
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oxygen has an atomic number of 8. what can you conclude from this fact?…
D. An atom of oxygen has 8 protons.
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question 7 1 pts atoms that vary in the number of neutrons found in the…
B. Isotopes
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what do electrons in the same shell have in common? they have the same …
A. They have the same amount of energy.
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what is the significance of the periodic table of elements? choose the …
B. It predicts and lists all the chemical elements in the universe. (Here we assume the second option is labeled as B, if the original options have different labels, adjust accord…
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question 11 an example of a compound is ○ salt (nacl) ○ sodium (na) ○ c…
A. Salt (NaCl)
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choose all of the following that are compounds. water (h2o) carbon diox…
- water ($H_2O$) - carbon dioxide ($CO_2$) - Hydrochloric acid (HCl)
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______ are substances with constant composition that are made of elemen…
C. Compounds
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a compound is ○ a pure substance that cannot be broken down into simple…
B. a pure substance made of two or more types of atoms that are chemically bonded together.
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water’s chemical formula is \h₂o.\ what does this mean? ○ water is comp…
A water molecule contains two hydrogen atoms and one oxygen atom.
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what is a compound? a compound is a substance made up of two or more el…
A. a compound is a substance made up of two or more elements
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some iron and sulfur are mixed together, then heated. when the result i…
A. compound
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question 5 what is vanillin (c₈h₈o₃) ? (this is what smells like vanill…
A. Compound
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what happens to the chemical formula and structure of water when it cha…
D. Nothing happens to the chemical formula and structure.
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in what way are liquids different from solids? liquid molecules are lig…
C. Liquids don't have a fixed shape; solids do.
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what is hydrogen peroxide (h₂o₂) ? compound element homogeneous mixture…
A. Compound
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1 multiple choice 1 point what is matter? choose the best answer anythi…
B. Anything that takes up space
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check all of the following that are mixtures ☐ air ☐ distilled water (h…
- Air - Ocean water (H2O, NaCl, KCl, etc) - Tree leaves
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determine the electron configuration of: 1) o²⁻ e⁻= 10 p⁺= 8 n⁰= 10-8= …
$e^- = 10$, $p^+ = 8$, $n^0 = 8$, Electron Configuration: $1s^2 2s^2 2p^6$ ### 1. For $\boldsymbol{N}$ (Nitrogen):
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question 1 which of the following is a compound? phosphorus trichloride…
A. Phosphorus trichloride (PCl) (Note: Correct formula should be PCl₃, but among the given options, this is the compound as it consists of different elements chemically combined)
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question 6 1 pts if xenon has an atomic number of 54 and a mass number …
### Question 6 # Explanation: ## Step1: Recall neutron formula The number of neutrons ($n$) is calculated by the formula $n = \text{mass number} - \text{atomic number}$. ## Step2:…
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a silver necklace reacts with sulfur in the air which make... (partiall…
\(2\text{Ag}\) and \(\text{S}\) ### For "Which chemical formula(s) represents the products?"
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take quiz exit question 4 1 pts true or false: molecules with the formu…
False ### Question 5
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3. mg e⁻ = ____ p⁺ = ____ n⁰ = ______ electron configuration: no. of sh…
\( e^- = 12 \), \( p^+ = 12 \), \( n^0 = 12 \) Electron Configuration: \( 1s^2 2s^2 2p^6 3s^2 \) No. of Shells = 3, Valence \( e^- = 2 \) ### For 4. \( \text{Mg}^{2+} \):
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consider the figure below: atomic number 6 c 12 chemical symbol 6 c 13 …
carbon - 12: 6 neutrons; carbon - 13: 7 neutrons
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consider the figure below: figure showing electron shell diagrams for e…
1 (corresponding to the option "1" or the option with the text "1" among the choices, which in the given options is the one marked with the blue dot: "1")
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how many electrons do elements in groups 14 and 17 need to gain to achi…
Elements in group 14 need to gain 4 electrons and elements in group 17 need to gain 1 electron.
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name _________________________________________ polymer lab step 3- hypo…
An inference is a conclusion made from observations/evidence. A hypothesis is a testable prediction (often in an “if - then” format) made before an experiment to be tested.
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3. what is the value of n in the equation 2.6 × 10⁻² = (5.2 × 10⁷) ÷ (2…
\(n = 9\) ### Question 4
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step 3- hypothesis and variables think back to the original day of poly…
Inference: Conclusion from evidence/observations. Hypothesis: Testable prediction for an experiment. ### Hypothesis Completion (Example)
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1. identify the element. 2. identify this element. 3. identify the elem…
Zirconium (Zr) ### Problem 3:
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links. www.scilinks.org topic: origin of elements code: hk81082 section…
Mendeleev organized his periodic table by arranging elements in order of increasing atomic mass and grouping elements with similar chemical properties in vertical columns (groups)…
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this energy in the form of light. what happens to the electrons as the …
1. Electrons exist in discrete energy levels (orbitals) with specific energy values around the nucleus. 2. The nucleus is composed of protons (positive charge) and neutrons (neutr…
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no balanced chemical equation a silver necklace reacts with sulfur in t…
\(2\text{Ag}\) (Silver) and \(\text{S}\) (Sulfur) ### 2. Which chemical formula(s) represents the products?
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c:1 h:2 o:3 is this a balanced equation (yes or no)? explain why
No. A balanced chemical equation requires the number of each type of atom (C, H, O here) to be equal on both the reactant and product sides. The given data shows atom counts for o…
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4. calculate the atomic mass of lead. the four lead isotopes have atomi…
The atomic mass of lead is approximately 207.22 amu (rounded to two decimal places).
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multiple select question select all that apply which of the following a…
A. acesulfame - K, B. neotame, D. aspartame
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energy → c₆h₁₂o₆ + o₂ which chemical formula(s) represents the products…
\(C_6H_{12}O_6\) and \(O_2\) ### Second Sub - Question: How many of each atom is present in the products?
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what do these two changes have in common? dry ice sublimating and becom…
Both are only physical changes. Both conserve mass. (Note: "Both are caused by heating" is incorrect for pouring milk on oatmeal (it’s a physical mixing, not necessarily caused by…
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what do these two changes have in common? a log decomposing in the wood…
Both conserve mass. Both are chemical changes. (Note: The options "Both are caused by cooling" and "Both are changes of state" are incorrect. Log decomposition (rotting) and snail…
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what do these two changes have in common? an engine using gasoline to p…
Both conserve mass, Both are chemical changes. (Note: The options "Both are caused by heating" and "Both are caused by cooling" are incorrect. The engine using gasoline involves c…
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what do these two changes have in common? a dinosaur bone turning into …
The correct option is: Both are chemical changes.
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what do these two changes have in common? adding dish soap to water in …
A. Both are only physical changes.
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directions: read chapter 15 section 2- click here from the red earth sc…
To solve this fill - in - the - blank problem about Earth's energy and heat transfer, we analyze each blank based on the context and the word bank: ### Blank 1: The sun is the pri…
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what do these two changes have in common? a copper statue turning green…
B. Both are chemical changes
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what do these two changes have in common? dew appearing on grass in the…
A. Both are only physical changes
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what do these two changes have in common? stapling an envelope shut san…
A. Both are only physical changes.
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select and drag each item to the correct area. diethylene glycol, tar, …
Vape Juice Ingredients: Diethylene glycol, Ammonia, Diacetyl Cigarette Ingredients: Tar (Note: Tin seems out of place here, maybe a mistake in the question. If we have to place it…
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4. calculate the atomic mass of silicon. the three silicon isotopes hav…
The atomic mass of silicon is approximately \( 28.09 \) amu (more precise calculation: \( 27.9769\times0.922297 + 28.9765\times0.046832 + 29.9738\times0.030872 = 27.9769\times0.92…
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what do these two changes have in common? a puddle freezing into ice on…
A. Both are only physical changes.
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5 plant cells use water, carbon dioxide and en and oxygen this process …
$CO_2$, $H_2O$ ### Sub - question 2: How many of each atom is present in the reactants?
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diacetyl is... ○ ...an ingredient in vape juice that is not good to inh…
C. ...an ingredient that is considered safe in some foods to eat, but is not safe to inhale into the lungs.