Química
Reacciones químicas, estequiometría, estructuras moleculares y propiedades.
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check your understanding... select the correct answer and click submit.…
Can create both physical and health risks
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True
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Get you the information you need to work safely with and around chemicals
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Is a fire hazard
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B. False
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Is toxic or fatal
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False
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which statement is true of all organic compounds? all contain carbon. a…
All contain carbon.
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the metal displayed in the structure of house in kamiyama by kazuto nis…
A. synthesis
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1. the three main surface processes are weathering, erosion, & depositi…
1. weathering, erosion, deposition 2. Weathering is the chemical or physical breakdown of rock. 3. Chemical 4. Physical (mechanical) 5. Various environmental movements like wind, …
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4. how many orbitals does an s sub - orbital have? 1 2 3 2. how many bo…
1. 1 2. 1
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14. what element does this orbital diagram represent? na n ni 7. how ma…
N ### 7.
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11 what is an octet? a valence electrons 8 electrons 8 people singing 3…
1. 8 electrons 2. 1s²2s²2p⁶3s²3p⁶4s²3d¹⁰ 3. Be
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which product, according to fda labeling, is raw, unprocessed, contains…
fresh grapes
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1. how many valence electrons does the element krypton have? 20. are sh…
1. C. 8 2. A. Yes 3. (There is an error in options. If it was meant to be As, that would be the answer. But among given options, no correct answer)
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1/ what element does this orbital diagram represent? be b br 6. how man…
1. Be 6. 20 5. 2
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13 what letters represent the sub - levels? a,b,c,d,f,g s,p,d,f,g s,d,p…
C. Zn ### Question 12
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16. what element does this orbital diagram represent? ca co c
C. C
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16. what element does this orbital diagram represent? ca co c
C. C
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choose the statement that best describes the space between the stars in…
The space between the stars contains nebulae and other structures of gas and dust.
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question 12 of 19 > which of these statements are true of molecular clo…
True: detected using tracer molecules such as CO, composed of mainly hydrogen, can collapse due to their own gravity False: can contain up to a hundred solar masses of gas (can be…
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2. voici différentes concentrations de solutions. transforme les unités…
a) 4000 g/l b) 0.5 g/l c) $4\times10^{-3}$ g/l d) 62.5 g/l e) 50 g/l f) 25 g/l g) 22500 g/l h) 0.36 g/l i) 7000 g/l j) 500 g/l
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the freezing point of a liquid is the temperature at which it freezes, …
salt water
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select all of the following that can be causes for extreme emotions. ce…
- certain diseases - drug use - chemical imbalance
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current attempt in progress the actual mass of an atom of cl is 5.886×1…
B. $1.70\times 10^{23}$ atoms
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the number of subatomic particles represented by $_{79}^{197}au^{3 + }$…
C. 79, 118, 76
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the sixth graders at palm valley school just finished a chemistry unit …
2
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current attempt in progress the isotopic notation for an isotope that h…
$_{35}^{81}Br$
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current attempt in progress identify the element, with name and chemica…
B. sodium, Na
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current attempt in progress the atomic number for iron is: o 26. o 55. …
26.
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according to the law of definite composition, water contains 8 grams of…
4 grams of hydrogen.
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current attempt in progress protons are: o electrically neutral. o smal…
None of the above options are correct.
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current attempt in progress explain why the mass number of an element i…
The mass number is equal to the sum of the number of protons and the number of neutrons in an atom. It is not possible to have a fraction of a proton or neutron in an atom, thus t…
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fill in the blank question any molecule that triggers an immune respons…
antigen
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current attempt in progress in what ways are isotopes alike? in what wa…
Isotopes contain the same number of protons. Isotopes have different numbers of neutrons and thus different atomic masses.
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current attempt in progress what letters are used to designate atomic n…
$Z$ represents the atomic number. $A$ represents the mass number.
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(c) what is the atomic number of phosphorus? (d) what is the atomic num…
(d) 88 (e) 30
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(a) what is the atomic number of copper? (b) what is the atomic number …
(a) 29 (b) 7 (c) 15
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multiple choice question the process of coagulation uses many biochemic…
B. clotting
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current attempt in progress from the chemists point of view, what are t…
Protons are positively - charged and located in the nucleus. Neutrons are neutral and located in the nucleus. Electrons are negatively - charged and orbit the nucleus.
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current attempt in progress from the chemists point of view, what are t…
Protons are positively - charged particles found in the nucleus with significant mass. Neutrons are neutral particles in the nucleus with mass similar to protons. Electrons are ne…
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view policies current attempt in progress how do anions and cations dif…
a) Cations have a positive charge and have fewer electrons. b) Anions have a negative charge and have more electrons.
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question 9 of 25 according to the implied consent law: a a driver under…
D. All of the above are true.
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view policies current attempt in progress distinguish between an atom a…
An atom is electrically neutral, containing equal numbers of protons and electrons. An ion has a charge resulting from an imbalance between the numbers of protons and electrons.
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10. gay - lussacs law shows a direct relationship between: a. pressure …
C. Pressure and Temperature ### 11.
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incorrect. do masses have any effect on how chemical formulas are writt…
Atoms combine to form compounds in simple numerical ratios, such as one to one, one to two, etc.
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which statements of daltons theory explain why chemical formulas are al…
Atoms combine to form compounds in simple numerical ratios, such as one to one, one to two, etc.
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current attempt in progress complete the following statements of dalton…
a) indivisible b) mass c) masses d) compounds e) ratios f) elements
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a particular element exists in two stable isotopic forms. one isotope h…
Atomic mass: $63.35$ amu (rounded to two decimal - places) Symbol of element: Cu
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the shape of your eye is one of the factors that determine how well you…
1. A. True 2. A. True
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naturally occurring zirconium exists as five stable isotopes: $^{90}zr$…
$91.23$ amu
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current attempt in progress naturally occurring zirconium exists as fiv…
$91.21$ amu
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(c) calculate the mass of the 2 electrons gained by oxide anion in atom…
c) $1.09716\times 10^{-3}$ d) No, the mass of an oxygen atom does not change significantly when it gains electrons to become an anion because the mass of electrons is extremely sm…
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multiple choice question plasma contains chemicals called ______ which …
C. electrolytes
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oxygen atoms tend to gain 2 electrons to form oxide anions. (a) what is…
(a) - 2 (b) 16
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type the correct answer in each box. the atomic number of sodium (na) i…
15, 15
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current attempt in progress an unknown element contains 33 protons, 36 …
a. 33 b. Arsenic, As c. 43 d. - 3, anion e. $_{33}^{76}As$
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incorrect. what given information can be used to find the atomic number…
Protons: 19 Neutrons: 20 Electrons: 19
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(b) $^{32}s$ protons neutrons electrons (c) manganese - 55 ($^{55}mn$) …
For $^{32}S$: Protons: 16 Neutrons: 16 Electrons: 16 For $^{55}Mn$: Protons: 25 Neutrons: 30 Electrons: 25
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select the correct answer. which chemical reaction absorbs energy? a. p…
A. photosynthesis
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select the correct answer in this equation stands for carbon, stands fo…
D. 2CO + 2NO → 2CO₂ + N₂
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give the number of protons, neutrons, and electrons in the following is…
Protons: 29 Neutrons: 34 Electrons: 29
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write isotopic notation symbols for each of the following. (a) z = 29, …
$\ce{^{65}_{29}Cu}$
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in this section, i will write about the benefits of eating organic food…
Weak: Not a Claim
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question 7 of 30 view policies current attempt in progress write isotop…
(a) $\ce{^{65}_{29}Cu}$ (b) $\ce{^{45}_{20}Ca}$
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select all the correct answers. copper is listed in the 29th position i…
a. a metal, e. an element
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view policies current attempt in progress what part of the atom contain…
nucleus
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select all the correct answers. which changes will increase the rate of…
adding more oxygen to the reaction, changing the reactants from solid form to powdered form
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what do an ion of ca and an atom of ar have in common? an ion of ca²⁺ a…
A. An ion of Ca²⁺ and an atom of Ar have the same number of electrons, but a different number of protons and neutrons in their atoms.
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end of semester test: physical science a classify the sentences based o…
| Synthesis | Decomposition | Replacement | |-----------|---------------|-------------| | Sodium (Na) reacts with chlorine (Cl) to give sodium chloride (NaCl); A strip of magnesiu…
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which subatomic particles are not in the nucleus? etextbook and media w…
1. Electrons 2. An ion of $Ca^{2+}$ and an atom of Ar have the same number of electrons.
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complete the following table with the appropriate data for each isotope…
| Element | Symbol | Atomic number | Mass number | Number of protons | Number of neutrons | Number of electrons | | ---- | ---- | ---- | ---- | ---- | ---- | ---- | | chlorine | $…
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drag each label to the correct image. each label can be used more than …
lemon juice pH 2.2: acidic salt solution pH 7: neutral baking soda pH 9: alkaline bleach pH 13: alkaline tomato juice pH 4: acidic gastric juices pH 1: acidic
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select the correct answer to determine whether a chemical reaction has …
D. density
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current attempt in progress complete the following table with the appro…
| Element | Symbol | Atomic number | Mass number | Number of protons | Number of neutrons | Number of electrons | | ---- | ---- | ---- | ---- | ---- | ---- | ---- | | Chlorine | $…
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current attempt in progress your answer is partially correct. how is it…
The properties of an element are related to the number of protons and electrons. If the number of neutrons differs, isotopes result. Isotopes of an element are still the same elem…
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current attempt in progress how is it possible for there to be more tha…
neutrons; atomic mass
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drag the tiles to the correct boxes to complete the pairs. identify the…
methane + oxygen → water + carbon dioxide + heat: combustion reaction of fossil fuels glucose + oxygen → carbon dioxide + water + energy: respiration water + carbon dioxide + sunl…
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question 1 of 30 view policies current attempt in progress given the fo…
The first and the second elements are isotopes.
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select the correct number the equation shows neutralization of an acid …
2
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physical vs. chemical change quick check which of the following is a re…
conduct a test to determine the chemical makeup of the molecules
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physical vs. chemical change quick check which of the following demonst…
Iron (Fe) reacting to water ($H_2O$) and oxygen (O) to form iron oxide ($Fe_2O_3$)
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select the correct boxes. which two elements have the same number of va…
silicon, carbon
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select the correct answer. daryl looks at a bottle of what looks like c…
C. heterogeneous mixture
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end of semester test: physical science a choose the image where a chemi…
The image labeled "Water boiled" (third image) where a chemical reaction has not taken place.
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physical vs. chemical change quick check which of the following is an e…
dry ice becoming vapor
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question 1 even though fingerprints typically remain unchanged througho…
Question 1: Severe burns, chemical burns, or repeated industrial - work - related friction can cause loss or alteration of fingerprints. Question 2: Many apps collect location dat…
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fill in the blank question biochemicals released by leukocytes cause an…
inflammatory
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question 21 of 23 view policies show attempt history current attempt in…
D. 15.4 g
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magnesium oxide, mgo, is 60.3% magnesium. how much magnesium is contain…
15.4 g
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current attempt in progress a 7.455 g sample of kcl contains 3.545 g of…
52.45%
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current attempt in progress of the properties listed below for the meta…
ignites when heated
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aphing in science home school chemis... sey chemistry the vertical axis…
B. Coordinate grid
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view policies current attempt in progress what is the common characteri…
hydrogen, carbon
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predict which would produce more carbon dioxide when burned, a molecule…
A molecule of octane would produce more carbon dioxide when burned because it contains more carbon atoms than ethane.
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which requires more energy to heat from 20 °c to 30 °c, iron or gold? (…
Iron, specific heat capacity
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how is a chemistry calorie (cal) different from a food calorie (cal)? 1…
1; 1000
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current attempt in progress what is the fundamental difference between …
A new substance is always formed during a chemical change, but never formed during physical changes.
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5. wind causes weathering and erosion because it a transports chemicals…
B. transports particles.
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what are steps you should take before finding the absorbance of any of …
- wipe with Kim wipe - place cuvette in spectrophotometer, orientation matters - calibrate with solvent of solution being tested