Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
-
14. explain how each of the following affects the amount of h₂ present …
a. The amount of $H_2$ decreases. b. The amount of $H_2$ increases. c. The amount of $H_2$ remains unchanged. d. The amount of $H_2$ remains unchanged. e. The amount of $H_2$ rema…
-
13. consider the following reaction: mathrm{hconh}_{2}(mathrm{g})=mathr…
$5.62\ atm$
-
12. equilibrium is established in a 2.50 l flask at 250 °c for the foll…
$[PCl_5]=0.191\ M$, $[PCl_3]=0.249\ M$, $[Cl_2]=0.0291\ M$
-
what is the difference in energy (in joules) between the n = 5 and n = …
$4.90\times 10^{-20}$ ### Question 2
-
a solution has a ph of 8. which best describes the solution? a strong a…
a weak base
-
jose needs 6.2 lb of organic blueberries to make smoothies. organic blu…
Jose incorrectly rounded $2.85$ down to $2$. The estimate should be $18$. So the correct option is: Jose incorrectly rounded $2.85$ down to $2$. The estimate should be $18$.
-
schemas can bias an individuals perception toward identifying specific …
C. perceptual set
-
type the correct answer in the box. express your answer to three signif…
20.4
-
according to the us food and drug administration (fda) what must any pr…
at least 95% organically produced ingredients
-
gabriella stops into a convenience store to find a healthy snack and se…
check the bottle's nutritional label to determine if all the ingredients are healthy
-
objective: you will explore the unique properties of hydrogen bonds and…
Shade the large circles (oxygen atoms) red and the small circles (hydrogen atoms) white. Label the oxygen atoms with $\delta^-$ and the hydrogen atoms with $\delta^+$. Label the s…
-
the atomic radius of a cesium atom is 0.000298 micrometers. round this …
\(3\times10^{-4}\)
-
how is an atoms net charge determined? a by the size of the atomic nucl…
B. By the relative number of protons and electrons.
-
a neutral atom of lithium has 3 protons. what can you infer about the n…
The lithium atom has lost an electron, so it now has 3 protons and 2 electrons.
-
objective: you will explore the unique properties of hydrogen bonds and…
Shade oxygen atoms red and hydrogen atoms white. Mark $\delta-$ on oxygen atoms, $\delta+$ on hydrogen atoms. Label solid lines as covalent bonds and dashed lines as hydrogen bond…
-
what term is introduced in lesson 3 to describe the push/pull interacti…
A. Force(s)
-
looking at the same nonmetal group on the periodic table, how does the …
The period 2 element would be more reactive because the attractive force of protons is stronger when electrons are attracted to a closer electron shell.
-
regular chemistry instructions: using your notes, and periodic table an…
1a. As 1b. As (assuming same elements as 1a) 1c. Sc 1d. O 1e. At 2a. Na 2b. P, S 2c. Si 2d. F, Cl 2e. He 2f. Ag, Cu 2g. Cs 2h. Na, Cs 2i. O 3a. The energy required to remove an el…
-
exposure of the skin to heat, chemicals, or electricity may result in m…
C. burns
-
11 multiple choice 1 point what is the most common size for phillips sc…
11. 2 12. The date the chemical was originally patented
-
learning study guide you will want to have an understanding of the voca…
1. Pavlov's study demonstrated classical conditioning and how behaviors can be learned through association. 2. - Initial stage of learning; response is first established and gradu…
-
a 54.0 - kg cheetah accelerates from rest to its top speed of 30.5 m/s.…
(a) $25116.75$ J (b) $6.0$ calories
-
chemical bonding jewelers use gems in jewelry because of their appearan…
1. | Gems | Metals | |--|--| | Hard, brittle, high refractive index (luster) | Malleable, ductile, good conductors of heat and electricity | 2. In metals, delocalized electrons in…
-
substance chemical formula element 1 symbol; metal/non metal element 2 …
# Explanation: ## Step1: Identify elements and bonding type for sulfur dibromide Sulfur dibromide has formula $SBr_2$. Sulfur ($S$) is a non - metal and bromine ($Br$) is a non - …
-
9. how many protons, neutrons and electrons are in this element? 10. la…
Protons: 9, Neutrons: 10, Electrons: 10
-
nancy has a home - based business selling herb and spice mixes. she is …
770 grams of French sea salt 330 grams of dried herbs
-
for a college chemistry experiment, students need to prepare a solution…
8.6
-
a teaching assistant at a university needs 28% acid solution for her cl…
75
-
show how many valence electrons each of the following elements have usi…
Sulfur: 6 valence electrons, dot - diagram with 6 dots around 'S' Strontium: 2 valence electrons, dot - diagram with 2 dots around 'Sr' Silicon: 4 valence electrons, dot - diagram…
-
substance;element 1 symbol; metal/nonmetal;element 2 symbol; metal/nonm…
Completed table as above.
-
drag each label to the correct location on the image. identify the four…
- Reactants: The substances at the lower - left part of the graph with initial energy. - Activation energy: The vertical distance from the energy level of reactants to the peak of…
-
multiple choice question misty begins her conclusion by saying, \my pur…
She relates to the audience by saying, "these benefits extend not only to you but also to the environment."
-
1. which of the following must be worn during the lab? a. goggles b. ap…
1. d. All of the above 2. c. Chemical energy 3. Graduated cylinder; Volumetric flask 4. Higher temperature region; Lower temperature region 5. Campfire burning: Exothermic; Ice me…
-
for each of the following elements, provide the correct electron config…
5. Electron - configuration: $1s^1$, Valence electrons: 1 6. Electron - configuration: $1s^22s^22p^63s^23p^6$, Valence electrons: 8 7. Electron - configuration: $1s^22s^22p^63s^23…
-
when should you wear ppe to protect yourself from chemical hazards? sel…
B. Whenever chemical hazards are present
-
assignment 1. page 8 of your text shows the various states of water. us…
| Behavior Of Particles (water Molecules) | Gas (Water Vapor) | Liquid (Water) | Solid (Ice) | | ---- | ---- | ---- | ---- | | How close are the particles | Far apart | Closer tha…
-
select the correct answer. which orbitals can overlap to form a pi bond…
A. two p orbitals
-
ideal gas law pv = nrt universal gas constant r = 0.0821 l·atm/(mol·k) …
1. First, find the molar mass of \(HCl\). The molar mass of \(H = 1.008\ g/mol\) and \(Cl=35.45\ g/mol\), so \(M_{HCl}=1.008 + 35.45=36.458\ g/mol\). - The number of moles of \(HC…
-
gas laws fact sheet ideal gas law pv = nrt ideal gas constant r = 8.314…
C. 16.4 L
-
select the correct answer. which description is true of 0.02 m ca(oh)₂ …
B. It's a dilute strong base.
-
select the correct answer. which sentence is true of all brønsted - low…
B. They can accept a hydrogen ion.
-
common polyatomic ions chemical name chemical formula chemical name che…
A. 353.5 g
-
15 select the correct answer from each drop - down menu. consider the s…
The boiling point of HF is higher than the boiling point of H₂, and it is higher than the boiling point of F₂.
-
type the correct answer in the box. isopropanol (c₃h₈o) is a key ingred…
$1.74$
-
select all that apply select all features of saturated fats. contains d…
C. Are most commonly found in animal fats D. Contain only single carbon bonds E. Are solid at room temperature
-
select all the correct answers. what are the products of the acid - bas…
B. $H_2O$, D. $LiClO_3$
-
h | h - al - h | h h | :f - c - f: | h h - p - h | h :ö=ö - ö:
1. tetrahedral 2. tetrahedral 3. trigonal - pyramidal 4. bent
-
the law that states that a compound is always composed of the same elem…
the law of definite proportions
-
read the excerpt from the author to her book. thou ill - formd offsprin…
A. A, A, B, B
-
an element ... (select all that apply) contains different atoms. can be…
- is a substance. - cannot be broken down.
-
select the correct answer from each drop - down menu. to prepare a 2 m …
The mass of the solute and the volume of the solution must be measured. So the first - drop down menu: solute; the second - drop down menu: solution.
-
common polyatomic ions chemical name chemical formula chemical name che…
C. 151 g
-
choose all the statements that are true for mixtures. (select all that …
- Mixtures can contain pure substances. - Homogeneous mixtures are also called solutions. - There are 2 types of mixtures. - Mixtures can be formed from 2 gases together. - Two el…
-
13 of 16 04:42 / 40:00 __________ can be broken down into simpler subst…
D. compuestos
-
the type of mixture that has a constant composition throughout is a ___…
homogeneous mixture
-
which of the following are pure substances? select all that apply water…
- Water - Oxygen
-
synthetic materials o have only negative effects on the environment o a…
have no similarity to materials in nature
-
choose the statements that are true for \substances\. (select all that …
- Substances have an unchanging composition - An element is a substance.
-
the _____________ organizes the elements into periods and groups. ○ per…
periodic table
-
elements in the same group have similar physical and chemical propertie…
True
-
1. it is a branch of mathematics that uses letters, symbols, and number…
1. A. Algebra 2. B. Algebraic Expression
-
select the correct answer from each drop - down menu. describe the char…
The bond polarities are polar, the molecular shape is trigonal - pyramidal, and the molecule is polar.
-
the law that states that two compounds can be formed by the same elemen…
# Breve Explicación: La ley de múltiples proporciones establece que cuando dos elementos se combinan para formar más de un compuesto, las masas de uno de los elementos que se comb…
-
a ____________ is made up of two or more different elements that are co…
compound
-
select the correct answer. which pair of elements can form ionic bonds?…
E. potassium (K) and bromine (Br)
-
a ____________ is a combination of two or more pure substances in which…
A. mixture
-
darius buys a bottle of a chemical solution that contains 70% alcohol. …
350
-
h₂o (water is a(n) ... ○ compound that contains 2 atoms of hydrogen and…
compound that contains 2 atoms of hydrogen and one atom of oxygen.
-
type the correct answer in the box. a pharmacist works with a 1.75 m so…
147
-
sodium chloride (nacl) contains... one atom of sodium and three atoms o…
1 átomo de sodio y 1 átomo de cloro
-
type the correct answer in the box. express your answer to two signific…
14
-
a period is a vertical column in the periodic table. true false
False
-
select the correct answer. megan prepares a pitcher of lemonade by addi…
C. Stir the water continuously
-
select the correct answer. a solution has a ph of 4.20. using the relat…
E. 1.6×10⁻¹⁰ M
-
drag each tile to the correct box. match the name of each compound to i…
$H_2SO_3$ → sulfurous acid $NH_3$ → ammonia $HNO_3$ → nitric acid $H_2SO_4$ → sulfuric acid $HClO$ → hypochlorous acid
-
explain the common characteristics that all synthetic materials share. …
Synthetic materials are sourced from petrochemicals or other chemical precursors. The production process is typically polymerization. Common characteristics are durability, resist…
-
match the vocab with their definitions. a measurement that refers to th…
synthetic material: A material obtained from a natural material that has undergone a chemical reaction. composite: Something made of several materials. mass: A measurement that re…
-
which statement best explains why a metal atom and a nonmetal atom are …
Metal atoms have low ionization energy, and nonmetal atoms have high electronegativity, so electrons transfer easily from the metal atom to the nonmetal atom.
-
which statement describes the valence electrons in ionic bonds? they ar…
They are transferred from one atom to another.
-
which of these is a property of a substance that is composed of atoms t…
It can be flattened and bent.
-
what will most likely happen when two bromine atoms bond together? the …
A covalent bond will hold them together.
-
which statement explains why the bonds between nonmetals tend to be cov…
C. They have small differences in electronegativity.
-
when heated, calcium carbonate goes through a chemical reaction, and pr…
A. Carbon dioxide is produced, and as a gas, it was not captured to measure.
-
consider the positions of carbon, nitrogen, potassium, and calcium on t…
C. nitrogen (N)
-
in a chemical reaction, atoms are rearranged to form new molecules. how…
A. It will stay the same no matter how the atoms are rearranged.
-
sugar is made up of clear, colorless crystals that dissolve easily in w…
It is made up of atoms that are held together by covalent bonds.
-
in atomic theory, new substances are formed when the atoms of other sub…
C. The amount of matter is conserved.
-
how is electronegativity related to covalent bonding? atoms must have s…
Atoms must have similar electronegativities in order to share electrons in a covalent bond.
-
robin and alex are discussing how water molecules form when hydrogen an…
B. The number of oxygen atoms is the same before and after the reaction.
-
q.15.how many moles of mg are there in 2.75g of mg? (7 p show your work…
$0.113\ mol$
-
which pair of elements would form an ionic bond? carbon (c) and oxygen …
B. strontium (Sr) and chlorine (Cl)
-
conservation of mass berny has a 0.15 - kilogram candle, a 1.00 - kilog…
B. 1.40 kilograms
-
which of the following best helps to explain why hexane has a higher bo…
D. Hexane molecules have electron clouds that are larger than those of methanol molecules.
-
conservation of mass the chemical reaction shown above takes place in a…
The total mass of the system remains constant.
-
which of the following lewis diagrams represents the substance that wou…
C. H - C - C - C - N - H (with hydrogens attached to carbons and lone - pairs on nitrogen)
-
o2, h2o, c3h8, cf4. of the substances listed above, which has the highe…
B. $H_2O$, because hydrogen bonds form between its molecules.
-
08:19 hide compound 1 compound 2 the structural formulas of two compoun…
D. Although there are dipole - dipole attractions among molecules of both compound 1 and compound 2, the -OH group in compound 2 allows strong hydrogen bonding.
-
the london (dispersion) forces are weakest for which of the following g…
A. $H_2$
-
in the chemical reaction below, sodium metal and chlorine gas combine t…
B. will be exactly 50 grams.
-
name: teacher: schools q1 chemistry: u2l7 avg. atomic mass & mass spec …
1. An unstable form of an element emitting radiation during decay to a stable state. 2. Due to unstable nuclei from proton - neutron imbalance. 3. Alpha - decay, beta - decay, gam…