Chemie
Chemische Reaktionen, Stöchiometrie, Molekülstrukturen und Elementeigenschaften.
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qe 6. which of the following is the metallic ion in sodium fluoride? f²…
\(Na^{1 +}\) (the fourth option)
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q 6. which of the following is the metallic ion in sodium fluoride? f 2…
$\ce{Na^{+}}$ (the option corresponding to $\ce{Na^{+}}$ in the given multiple - choice list)
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7. what is the formula for iron (ii) oxide? feo₂ fe₂o₃ feo fe₂o clear a…
FeO
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8. which of the following are true about metallic bonds? select two cor…
- "In metallic bonds, positive ions are attracted to electrons" is correct as the structure of metallic bonds involves positive ions (metal cations) and a sea of electrons. - "Met…
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9. which of the following is not a characteristic of metals that can be…
brittleness
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periodic table of elements in the compound ( xy_2 ), the element repres…
group 2 element, metal
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13. when a nonmetal is hit with a hammer it will crumble or break. meta…
malleability
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14. classify the following as either a metal, metalloid or a nonmetal: …
1. Metalloid 2. Metal 3. Metal
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17. what is the name for the compound na₃(po₄)?
Sodium phosphate
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2. what is the formula for sodium fluoride?
\(NaF\)
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1. which of the following properties would a substance that has metalli…
All of the properties (I, II, III, IV) are properties of a substance with metallic bonding.
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these two people are running. which best describes their energy? both e…
Both mechanical and chemical energy
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which type of energy would you get from eating a bowl of cereal? mechan…
Chemical energy
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to play soccer, what type of energy is needed by your muscles so they w…
chemical
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5. in mendeleevs new table, patterns in reactivity appeared to repeat a…
5. 8 6. Rows = periods; Columns = groups 7. - Predicted new elements (e.g., left gaps for them). - Corrected atomic masses of known elements. 8. Mendeleev predicted eka - aluminiu…
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dry ice, or solid carbon dioxide, is used for a number of tasks includi…
First question: sublimation Second question: hardness
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22. what is the rhyme scheme of shakespeares sonnets? a. aabbccddeeffgg…
B. ABABCDCDEFEFGG
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what must happen to the particles of a solid to allow it to become a li…
- First question: Particles move further apart, allowing the substance to melt. - Second question: gold.
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what is the best definition of a pure substance? a substance made of on…
a substance made of only one component
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why is copper a pure substance? because it is an element because it is …
Because it is an element.
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which of the following is an example of chemical reaction? putting milk…
an apple that turns brown after a bite is taken
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how can we tell this banana ripening is a chemical change? formation of…
A new color has appeared.
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which of the following is not an example of a chemical change? a piece …
a piece of paper being torn
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which of the following is a chemical change? creating a mixture of wate…
Baking brownies
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when you mix sugar into a glass of lemon juice until it disappears, the…
lemon juice
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which of the following shows an example of a heterogeneous mixture?
The image with the berries.
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which of the following is a homogenous mixture? cereal with milk ice cr…
green tea
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which of these is not a physical change? getting clothes wet burning a …
burning a candle
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what properties are changed when glass breaks? size and shape atoms and…
size and shape
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which action involving bread is a physical change? baking a loaf of bre…
Cutting a slice of bread
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which of the following examples is not considered a pure substance? fru…
fruit punch
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which of these is not a pure substance? lemonade h2o the element gold
lemonade
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which of the following is pure? air a solution an atom
an atom
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which of the following is a pure substance? heterogenous mixture homoge…
Element
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what is the best defnition of a pure substance? a substance made of onl…
a substance made of only one component
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1. the profits of an airline company can be modeled as ( p(t)=2(1.1)^t …
1. a. The profit in 2003 is \(3543122\) dollars. b. The \(y -\)intercept is \((0,2)\). It means in 1997, the annual profit was 2 million dollars. c. The first year is 2005. 2. a. …
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12 what are the six metalloids on the penodic table?--boron b silicon g…
a. Non - Metal b. Non - Metal c. Metalloid d. Metal e. Non - Metal f. Non - Metal
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periodic table unit review we will take the multiple choice test on thu…
a. 1 b. 3 c. 7 d. 8
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the milky way galaxy is composed of millions of stars in a relatively f…
A. There’s an age difference of about 2 billion years between certain stars in the thick disk.
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what did president abraham lincoln do in 1862 to help influence food re…
He appointed the first chemist to serve in the Department of Agriculture.
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atomic # = atomic mass = # of protons = # of neutrons = # of electrons …
- **For Lithium**: - Atomic # = \(3\) - Atomic Mass = \(6.941\) - # of Protons = \(3\) - # of Neutrons ≈ \(4\) - # of Electrons = \(3\) - **For Bromine**: - Atomic # = \(35\) - At…
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1. true or false - when zinc is immersed in hydrochloric acid, it produ…
1. False 2. A. Freezing 3. False 4. B. Vaporization 5. False 6. True 7. False 8. C. Sharpening a pencil 9. A. Melting 10. A. Chemical change
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test: covalent compounds which of the following is the correct formula …
\(\text{S}_4\text{N}_2\)
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test: covalent compounds how many valence electrons do the following at…
most atoms: 8, hydrogen: 2, helium: 2, boron: 6
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1. which of the following is an example of a physical change, but not a…
1. A. A water pipe freezes and cracks on a cold night 2. D. All of the above 3. True 4. True 5. True 6. No 7. D. Both A and C 8. B. Flammability 9. Physical properties
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test: covalent compounds sucrose (table sugar) is made of covalent comp…
low; poor
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test: covalent compounds which is the correct molecular structure for c…
The second option (the one with \(O = C = O\) and each oxygen having 2 lone pairs).
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test: covalent compounds covalent bonds form between and metals nonmeta…
nonmetals and nonmetals
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which of the following is the correct lewis structure for the compound …
The first option (the one with \(Br\) atoms having lone pairs and single bonds) is the correct Lewis structure for \(PBr_3\).
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test: covalent compounds which of these is the correct lewis structure …
D.
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test: covalent compounds why is this lewis structure incorrect? choose …
- B. There should only be single bonds in this Lewis Structure.
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test: covalent compounds the line in a lewis dot structure of a molecul…
two shared electrons
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test: covalent compounds how many more electrons does nitrogen need to …
3
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what is the correct structure for bf₃?
The second - option (the one with three single bonds between \(B\) and \(F\) atoms) is the correct structure for \(BF_3\).
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test: covalent compounds which electrons are involved in the formation …
valence electrons
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test: covalent compounds the formula for oxygen gas is shown. how many …
4
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test: covalent compounds which lewis dot model drawing correctly shows …
The second option (the one with two lines between the oxygen atoms and the correct number of lone pairs on each oxygen atom) is the correct Lewis Dot Model for \(O_2\).
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test: covalent compounds which is the correct name for p₃n₅? ○ phosphor…
B. Triphosphorus Pentanitride
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a group of scientists is studying the effect of a potentially toxic che…
Set the acceptable limits of the chemical low and keep them unless future studies show that they can be safely raised.
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fireworks operators usually fall into one of two camps: those who striv…
Text 1 suggests that many people enjoy loud fireworks while Text 2 discusses why quiet fireworks can be better.
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nitrogen gas (n₂) and hydrogen gas (h₂) combine to form ammonia (nh₃). …
N₂ + 3H₂ → 2NH₃
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which equation is balanced? ○ na + f₂ → 2naf ○ al + 3o₂ → al₂o₃ ○ mg + …
$2\text{Al} + 3\text{F}_2 \to 2\text{AlF}_3$
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if the amount of atoms of each type on the left and right sides of a re…
B. Coefficients are placed in front of the reactants and/or products.
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consider the equation: ch₄ + o₂ → 2h₂o + co₂ which element or elements …
Only the O is unbalanced.
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what does conserving mass mean in a chemical equation? there are more o…
There is equal number of each type of atom on the reactant and product side.
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law of conservation of mass name in chemical changes, no matter how big…
1. \(7.72\ g\) 2. \(8.96\ g\) 3. \(2.56\ g\) 4. \(b\) 5. \(d\) 6. \(100.9\ g\)
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21. prior to 1856, chicagos rapidly growing population and flat, swampy…
The frequent flooding and sewers dumping directly into the Chicago River and Lake Michigan.
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enter the units of the students answer. \\( \\frac { ( 0.36 \\mathrm { …
\(\mathrm{mol}\)
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3. you are asked to separate sand and sodium chloride. name the methods…
The methods needed are dissolution, filtration, and evaporation. First, dissolve the sand - sodium chloride mixture in water. Then, filter the mixture. The sand is retained on the…
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record an observation that describes the relationship between ions and …
Ions are formed when atoms gain or lose electrons, and ionic bonds are formed when oppositely charged ions attract each other.
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6 how does the presence of water affect ionic bonds? a water dissolves …
A. Water dissolves ionic bonds
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1. write the balanced chemical equation \\( \\mathrm { hc } _ { 2 } \\m…
The molarity of acetic acid is \(0.2335\ M\)
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7. mg (s) + zncl₂ (aq) ---> mgcl₂ (aq) + zn (s) 45.0 g 297.6 g 176.5 g?…
7. \(166.1\ g\) 8. \(125\ g\) 9. \(Mg\) 10. \(KCl\) 11. \(3\)
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3 fill in the blanks to complete the sentences. not all answer choices …
increases
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4 unlike neutral atoms, ions have charges because they have unequal num…
Substance B, Substance C
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instructions: determine the number of valence electrons in an atom of e…
7) helium: 2; 8) magnesium: 2; 9) sulfur: 6; 10) hydrogen: 1; 11) krypton: 8; 12) aluminum: 3
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the structure of a potassium atom is shown above. what kind of ion is i…
B. A positive ion, because it will give up an electron
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2 fill in the blank to complete the sentence. not all answer choices wi…
electrons
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1 according to the movie, what is an ion? a a type of bond that holds a…
C. An atom with a positive or negative charge
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example: elements in group 2 will have — valence electrons. elements in…
- "This desire to have 8 electrons in their outer energy level is called the octet rule." - "Atoms aim to have a full outer shell of electrons - usually 8." - "Elements in Group 2…
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valence electrons are the to know how many valence electrons an element…
Valence electrons are the electrons in an atom. To know how many valence electrons an element has, find the element on the periodic table. The group number indicates how many vale…
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name: what are valence electrons? period • valence electrons are the • …
- Valence electrons are the electrons in an atom's outer shell. - The group number (for main - group elements) on the periodic table indicates the number of valence electrons. - T…
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4. what happens when the difference in electronegativity between atoms …
4. A covalent bond forms. 5. Between 0.5 and 1.7.
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an aluminium isotope has 13 protons, 13 electrons, and 14 neutrons. wha…
C. 27
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4. potassium iodide is a salt used in some medicines. its chemical form…
D
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level 3 an atom consists of 8 protons and 6 neutrons. what is the total…
B. 8
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level 1 what are the particles that are found in the nucleus of an atom…
C. Protons and neutrons
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what is the region around the nucleus of an atom where electrons might …
C. Electron cloud
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level 5 a neutral atom becomes a positive ion when it a. gains an elect…
D. Loses an electron
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level 5 what term is used to describe the sharing of electrons between …
A. Chemical bond
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what is this sodium atom known as? a. isomer b. isotope c. anion d. ion
D. Ion
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a compound forms when or more things are combined to form something.
two, new
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2 when two ions meet, they bond together. use the table above to determ…
B. Ionic bond
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1 ion comes from a greek word that means \going\ or \something that goe…
B. They are active, likely to participate in reactions
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5 imagine that heavy rain soaks the salt pans in the video. what effect…
The piles of salt will dissolve.
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r×n types & balancing for each reaction below, balance the equation and…
1. \(1MgCl_{2}(aq)+2Na(s)\to 2NaCl(aq)+1Mg(s)\), RXN TYPE: SR 2. \(2H_{2}O_{2}\to 2H_{2}O + 1O_{2}\), RXN TYPE: (Not a valid type from the given COMBUST, SR, DR as it is a decompo…
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this image is a close - up of sea salt. which word best describes how s…
D. Crystallization
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gizmo warm - up rocks are classified by how they formed. the three type…
1. Sedimentary rocks 2. Metamorphic rocks 3. Igneous rocks
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student exploration: rock classification vocabulary: classify, extrusiv…
1. Sedimentary rock 2. Metamorphic rock 3. Extrusive igneous rock
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to collect salt this way, ocean water is channeled into large, shallow …
C. Salt dissolves in water but it does not evaporate