Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
-
4.1 - 4.2 review read this: for this review you will need: your journal…
1. See filled - in chart above. 2. Positive, determined by number of protons. 3. In the nucleus; protons and neutrons in nucleus have significant mass compared to electrons. 4. Pr…
-
the passage below discusses some of the steps of an engineering - desig…
Kari combines several different chemicals to create a test batch of the new window cleaner.
-
study guide chapter 6 section 1: atoms, elements, and compounds in your…
1. electron 2. energy level 3. neutron 4. nucleus 5. proton 6. false, symbol 7. false, groups 8. true 9. true 10. false, half - life 11. false, compound 12. false, ionic bonds
-
a nitride ion has 7 protons, 8 neutrons, and 10 electrons. what is the …
-3
-
which element has 16 protons in its nucleus? neon oxygen sodium sulfur
D. sulfur
-
in which block of the periodic table is uranium (u) found? s block d bl…
D. f block
-
the mass number of fe²⁺ is 56. how many neutrons are there in a single …
B. 30
-
boron occurs naturally as two isotopes. what is the difference between …
They have different numbers of neutrons and different mass numbers.
-
in which block of the periodic table is chromium (cr) found? o s block …
B. d block
-
the table below gives the numbers of protons, electrons, and neutrons i…
D. Atom 4
-
it is easier to determine the electron configurations for the p - block…
B. their electrons are assigned to s and p orbitals only.
-
which statement best describes john daltons use of creativity in his wo…
He reinterpreted and retested Joseph Proust's results.
-
esophagus: stomach: small intestine: large intestine: rectum: click on:…
22. A collection of glands that produce and secrete hormones directly into the bloodstream to regulate bodily functions. 23. Chemical messengers produced by endocrine glands that …
-
on: digestive system click on the diagram and describe each part of the…
The mouth is the initial part of the digestive system. It mechanically breaks down food by chewing and saliva starts the chemical digestion of carbohydrates while also moistening …
-
question 4 of 5 read the sentence from paragraph 2. all the next day th…
B. attempt
-
read the excerpts from lizzie bright and the buckminster boy. excerpt 1…
the only one for all the island's students.
-
if the temperature of a container of gas remains constant, how could th…
The number of gas molecules in the container increases.
-
question 7 1 pts what is the name given to the figure in which a line b…
Question 7: a paired orbital Question 8: Pauli
-
three quantum numbers for an electron in a hydrogen atom in a certain s…
Question 1: A. 4p Question 2: A. 18 Question 3: C. 15
-
three quantum numbers for an electron in a hydrogen atom in a certain s…
# Explanation: ## Step1: Identify orbital type from quantum numbers The principal quantum number $n = 4$ indicates the energy level. The angular - momentum quantum number $\ell=1$…
-
what block and what period are associated with the element sulfur, s? t…
1. the p block and the third period. 2. the d block and the fifth period. 3. 5 d; 5
-
good news: dont worry, we will be going over this information in much m…
A. the periodic table
-
the really good news is that when we are all through with the math for …
electrons repel each other.
-
an orbital is described by combining the n quantum number with the $l$ …
1. True 2. C. s
-
the third type of chemical bonding, metallic bonding, occurs between me…
- Valence electrons move freely throughout a metal. - Metallic bonding occurs between metal atoms.
-
consider the lewis dot structures of lithium and fluorine atoms. li ·f:…
$[\text{Li}]^{+}[\ddot{\text{F}}:]^{-}$ (the first option in the given choices)
-
6 of 13 which of the following is an example of the best way to manage …
"To sum up Megan's question, she's asking whether trees can cure pollution."
-
ionic compounds can be represented by bohr model diagrams and lewis dot…
Valence electrons are shown in the Bohr model of a sodium cation. A sodium cation has zero valence electrons. Both the Bohr model and the Lewis dot structure represent an ionic bo…
-
ammonia (nh₃) is a covalent compound. the nitrogen atom shares a pair o…
The first and fourth Lewis - dot structures are correct as they show the nitrogen atom bonded to three hydrogen atoms and have a lone - pair of electrons on the nitrogen. The seco…
-
covalent compounds can be represented by bohr model diagrams and lewis …
A. A chlorine molecule has 14 total valence electrons. D. There are two bonding electrons in a chlorine molecule.
-
reset the simulation (see directions between questions 3 and 4 if you n…
1. Sodium 2. The atomic radius decreases from left to right within the same period.
-
choose the elements magnesium (mg) and strontium (sr) from period 2. lo…
First question: B. Strontium Second question: A. Boron
-
which element appears larger in the side - by - side comparison? (see p…
1. Cesium 2. No answer (due to lack of lab - investigation data)
-
the \size\ of the atom: generally increases from top to bottom within a…
For the first description "The 'size' of the atom...": Atomic Radius For the second description "The amount of energy needed to remove an electron from an atom...": Ionization Ene…
-
compare the bohr model and lewis dot structure of an oxygen atom. the l…
All of the provided Lewis - dot structures for phosphorus are correct.
-
atoms tend to be stable when they have a full valence shell. most main …
2
-
atoms tend to be stable when they have a full valence shell. most main …
An oxygen atom is less stable than a neon atom. An oxygen atom will gain electrons to fill its valence shell.
-
atoms tend to be stable when they have a full valence shell. most main …
An oxygen atom is larger than a neon atom. An oxygen atom will increase its electron count by 2 to fill its valence shell.
-
the number of valence electrons that an atom has impacts its stability.…
Helium has 2 valence electrons, neon has 8 valence electrons, and argon has 8 valence electrons. All three noble gases have a full valence shell.
-
there are three types of chemical bonds: covalent, ionic, and metallic.…
A. A chlorine atom has seven valence electrons. B. Valence electrons can be shared between atoms or transferred from one atom to the other. D. Atoms combine by forming metallic, c…
-
sodium (na) is a gray, metallic solid that reacts strongly with water. …
B. When atoms of two different elements bond, they form a new compound with unique properties. D. In table salt, sodium and chlorine are held together by chemical bonds.
-
periodic table worksheet 1. tell which element is located in the follow…
a. Zirconium (Zr) b. Beryllium (Be) c. Tungsten (W) d. Helium (He) e. Tin (Sn) f. Zinc (Zn) g. Francium (Fr) h. Polonium (Po) i. Chlorine (Cl) j. Silver (Ag) k. Vanadium (V) l. Pl…
-
how do we classify matter? answer in 2 - 4 sentences, including the wor…
Matter can be classified as either a pure substance or a mixture. A pure substance can be an element (made of one - type of atom) or a compound (different atoms bonded).
-
3. vertical columns on the periodic table are called 4. horizontal rows…
3. Groups 4. Periods 5. Atomic 6. Mass 7. Ductility 8. Malleability 9. Transition metals 10. Alkali metals 11. Alkaline - earth metals 12. Noble gases 13. Halogens 14. 1 15. 17 16…
-
multiple - choice question true or false: water can be separated into d…
False
-
answer the following questions. choose the best answer. why should you …
Using a variety of sentence structures helps a piece of writing to be more interesting and smooth and less monotonous. Complex sentences help to show the connections among ideas a…
-
which of the following is true? this mixture only contains compounds. t…
It is impossible to determine which option is true without more information about the mixture.
-
multiple - choice question which statement best describes each group of…
They all contain 1 oxygen atom and 2 hydrogen atoms.
-
which of the following is true? this is an element, because its made of…
This is not an element, because it's made of more than one type of atom.
-
question 5 what substances will you observe the spectra for? select all…
A. Carbon B. Sodium C. Bromine D. Nitrogen
-
when is light emitted from an atom? when the nucleus absorbs energy whe…
When an electron goes from a higher energy orbital to a lower energy orbital.
-
which property would xenon most likely have? it is stable. it is a soli…
It is stable.
-
click on the link to go to the simul states of matter-p raise or reduce…
The state of matter is related to heat as adding heat can cause a substance to change from a solid to a liquid (melting) and then to a gas (vaporization), while removing heat can …
-
phet simulation. click solid, liquid, or gas to observe the behavior of…
It changes by the balance between the molecules energy. The molecules in solids have low energy and are in fixed positions. In liquids, they have more energy and can slide past on…
-
phet simulation. click solid, liquid, or gas to observe the behavior of…
The behavior of molecules changes in different states of matter due to the balance between molecular energy. Adding heat increases the energy of particles, which can cause a chang…
-
the half - life of indium - 111 is 67.2 hours. how many milligrams of i…
1.56 mg
-
conservation quick check what does the law of conservation of mass stat…
The total mass of all of the reactants prior to a chemical reaction must equal the total mass of all the products after the reaction.
-
conservation quick check if the mass of elements before a chemical reac…
30 grams
-
conservation quick check 78 g of potassium (k) react with 71 g of chlor…
149 g
-
conservation quick check 2 grams of potassium (k) reacts with 5 grams o…
7 grams (corresponding to the selected option in the original multiple - choice question)
-
conservation quick check which of the following equations demonstrates …
$CH_4 + O_2 ightarrow C + 2H_2O$
-
practice: americium - 241 is a radioactive isotope used in smoke detect…
$^{241}_{95}Am ightarrow^{237}_{93}Np + ^{4}_{2}He$
-
question 16 what is the stretching frequency (in cm⁻¹) of the following…
1655
-
what stretching frequencies (in cm^-1) are present in the structure bel…
all of these
-
the proper protective equipment for working with hazardous chemicals in…
T
-
you have been asked to write an essay about the effects of large amount…
Thesis statement: Americans consume large amounts of sugar in their daily diets, which leads to a variety of health problems. Supporting details: - The average American eats or dr…
-
fume hoods are used to ________ a. prevent fires from spreading in the …
C. prevent toxic gases from spreading through the lab
-
what is the stretching frequency (in cm⁻¹) of the following carbonyl? 1…
1715
-
what stretching frequencies (in cm⁻¹) are present in the structure belo…
1800
-
gas behavior gas pressure is a measure of the collisions of the molecul…
The gas pressures are: 760 mmHg, 900 mmHg, 585 mmHg.
-
aspartame: a has a low sweetness relative to sucrose. b has a trade nam…
# Breve explicación: El aspartamo es un edulcorante artificial ampliamente utilizado en bebidas sin azúcar debido a su gran dulzura. Es mucho más dulce que la sacarosa (sucrosa), …
-
chemistry - unit 1 - worksheet 4 dimensional analysis in the space belo…
2. 8.32×10^{-2} kg(\frac{10^{3} g}{1 kg}) = 83.2 grams 3. 55.5 mL(\frac{1 cm^{3}}{1 mL}) = 55.5 cm^{3} 4. 0.00527 cal(\frac{1 kcal}{10^{3} cal}) = 5.27×10^{-6} kilocalories 5. 9.5…
-
what is the stretching frequency (in cm⁻¹) of the following carbonyl? n…
D. 1685
-
recap/review 3.1 and 3.2 ws 1. if the accepted value is 8.8 and experim…
1. Percent Error: $44\%$ a) Calculator answer: $6.85\text{ cm}$, Answer with sig. figs: $6.9\text{ cm}$ b) Calculator answer: $3.374\text{ cm}$, Answer with sig. figs: $3.37\text{…
-
3. a student has a pool of water at 25 degrees c and a bucket of water …
a) Neither. The average speed of particles is the same because temperature is the same for both. b) Neither. The average energy per particle is the same because temperature is the…
-
chemistry—unit 2 review energy think of energy as a quantity that is al…
1a) False 1b) True 1c) False
-
what is the stretching frequency (in cm⁻¹) of the following carbonyl? 1…
1655
-
part 1 pennies and water question 1: how many drops of water did fit on…
1. Surface - tension is demonstrated. 2. The surfactant in soap reduces water's surface - tension, causing different results.
-
1. what property or properties of water is demonstrated by this activit…
1. The property of water demonstrated by this activity is surface tension. Water molecules have cohesive forces due to hydrogen - bonding, which causes them to stick together and …
-
what stretching frequencies (in cm⁻¹) are present in the structure belo…
1745
-
which of the structures have a major peak between 1700 and 3000 cm⁻¹? (…
First structure (acyl - chloride)
-
a student conducts an experiment to test how the temperature affects th…
the temperature of the water
-
which of the structures have a major peak between 1700 and 3000 cm⁻¹? (…
The first structure (acyl chloride)
-
which of the structures have a major peak between 1700 and 3000 cm⁻¹? (…
The first structure (acyl - chloride)
-
what is the stretching frequency (in cm⁻¹) of the following carbonyl? 1…
1745
-
a. the diameter of the sun is approximately 1.391×10⁶ kilometres. the d…
a. Approximately 109 Earths could fit along the diameter of the sun. b. There are approximately $5.487\times 10^{40}$ water molecules in Lake Ontario. c. Approximately $1.714\time…
-
which of the following is correct about icl a the name is iodine monoch…
A. The name is iodine monochloride and not monoiodine monochloride because the "mono" for the first cation - like element is dropped.
-
which of the following carbonyls have a stretching frequency around 168…
The second structure (the benzoate)
-
chemistry review & practice worksheet density & significant figures - s…
1. $7.6$ g/mL 2. $8.36$ g/cm³ 3. $11.0$ g/mL 4. $4.25\times10^{-4}$ kg 5. $3.5\times10^{-4}$ kg 6. $1.25\times10^{-3}$ kg 7. $\$43.05$ 8. $\$3.75$ 9. $\$1.80$ 10. Section 13 11. S…
-
a compound between p and br is ____ in nature and formed from ______ of…
D. covalent, sharing
-
what stretching frequencies (in cm⁻¹) are present in the structure belo…
E. all of these
-
the center section of the period table is classified into ___ elements.…
A. transition
-
what are the horizontal (from left to right) parts of the periodic tabl…
B. periods
-
the term periodic helps identify __________ that occur in the table, li…
C. patterns
-
the vertical columns in the periodic table are called a families b peri…
A. families
-
as you move from left to right across the periodic table, the number of…
A. Increases
-
varies from family to family on the periodic table a reactivity b speci…
A. Reactivity
-
elements in a family have the same ______________. a total number of el…
C. number of valence electrons
-
a is the name for a vertical column in the periodic table. a family b p…
A. family
-
which of the following carbonyls have a stretching frequency around 171…
The second structure (the cyclic ketone)