Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
-
water, air, buildings, food, and everything visible and invisible has m…
D. matter
-
building understanding one way to measure the amount of organic matter …
Long - term impacts relate to soil health and climate: - **Positive impacts (when soil carbon increases)**: Land use changes like “Crop to secondary forest” (+53%) and “Crop to pa…
-
12. the number of significant figures in the measured value 0.00320 g i…
b. 3
-
question 3 1 pts what element does the following noble gas configuratio…
A. rhodium
-
question 2 1 pts what is the noble gas configuration of phosphorus? ne …
B. $[Ne] 3s^2 3p^3$ (assuming the second option is labeled B; if the original labels were different, adjust the label but keep the configuration. From the image, the selected opti…
-
11. to two significant figures, the measurement 0.0255 g should be repo…
c. 0.026 g
-
question 1 1 pts how does the noble gas configuration shorten the elect…
C. By putting the previous noble gas in front of the remaining configuration (assuming the options are labeled A, B, C, D with C being the third option as described)
-
6. 0.25 g is equivalent to a. 250 kg. b. 250 mg. c. 0.025 mg. d. 0.025 …
b. 250 mg
-
select the correct answer. sodium bicarbonate is the chemical name for …
C. There are three atoms of oxygen in sodium bicarbonate
-
select the correct answer. a scientist conducts a chemical reaction. at…
C. The mass equals 11.7 grams because the system is closed.
-
is this chemical stable under normal conditions? what type of substance…
To answer these questions, we need to know the specific chemical in question. Chemical stability and incompatible substances depend on the chemical's identity (e.g., its molecular…
-
which material is the limiting ingredient if you have 12 cups of oats, …
walnuts (the option with "walnuts" as the text)
-
which material is the limiting ingredient if you have 24 cups walnuts, …
A. pecans
-
which material is the limiting ingredient if you have 4 pieces of sourd…
A. cheddar cheese
-
which material is the limiting ingredient if you have 2 cans of tomatoe…
tomatoes
-
how are nonmetals different from metals? recall that metals have luster…
Nonmetals are poor conductors of electricity and thermal energy. Solid nonmetals (at room temperature) have no luster. Many nonmetals are gases at room temperature. They are not d…
-
select the correct answer. potassium chloride is a white solid used in …
A. KCI
-
select the correct answer. carbon tetrachloride is a toxic liquid. a ca…
D. CCl₄
-
select the correct answer. nitrous oxide is the chemical name for \laug…
B. two nitrogen atoms and one oxygen atom
-
part ii: atom screen 1. click on the + sign for each of the boxes (elem…
Protons and neutrons ### Question 3: Play until you discover which particle(s) determine(s) the name of the element you build. Which particle is it?
-
3. fill in the blanks in the following table | substance | mass (g) | v…
| Substance | Mass (g) | Volume (\(cm^{3}\)) | Density (\(g/cm^{3}\)) | |-----------|----------|---------------------|------------------------| | X | 10.0 | 20.0 | \(0.5\) | | Y |…
-
air pollution global agreements several laws have evolved to address ai…
the United States
-
the melting point of an element is 5 times the melting point of radon. …
The melting point of the element is \(-350\) degrees Celsius.
-
7 multiple choice 1 point make the following conversion (1g = 1000 mg) …
A. 9.231 g
-
complete the names of these compounds. formula\tname fecl₂\tiron scl₂\t…
To solve this, we analyze each compound: ### For $\boldsymbol{FeCl_2}$: Iron (Fe) can have multiple oxidation states. In $FeCl_2$, Fe has a +2 oxidation state. When naming ionic c…
-
what is the density an 84.7 g sample of an unknown substance if the sam…
D. 1.7 g/cm³
-
which statement correctly describes glucose (c₆h₁₂o₆)? ○ it is made of …
It is a compound made of twenty - four total atoms.
-
what quantity does the measurement 37 mmol represent? ○ speed ○ volume …
C. amount
-
what volume would be occupied by 7.75 g of the substance with the densi…
4.53 $\text{cm}^3$ (the option with this value and unit, i.e., the third option: 4.53 $\text{cm}^3$)
-
looking at the graph, what is the independent variable? vapour pressure…
Temperature
-
basic atomic structure worksheet 1. the 3 particles of the atom are: a.…
a. Proton b. Neutron c. Electron Their respective charges are: a. \(+\) (positive) b. Neutral (no charge) c. \(-\) (negative) ### Question 2
-
there are four common oxoanions of iodine and two common oxoanions of n…
- $\ce{IO_4^-}$: periodate ion - $\ce{IO_3^-}$: iodate ion - $\ce{IO_2^-}$: iodite ion - $\ce{IO^-}$: hypoiodite ion - $\ce{NO_3^-}$: nitrate ion - $\ce{NO_2^-}$: nitrite ion
-
how many ml of liquid are in this burette? image of a burette with mark…
20.38 mL (the option: 20.38 mL)
-
the density of copper is listed as 8.94 g/cm3. two students each make t…
D. Student B is more accurate and precise than student A
-
a certain sample with a mass of 4.00 g is found to have a volume of 7.0…
\( 0.57 \) (the option with text "0.57")
-
what quantity does the following measurement represent: 9.4 g/mol ○ spe…
B. molar mass (assuming the options are labeled with letters, and the correct option is the one with "molar mass")
-
the chemical trimethylamine n-oxide not only gives fish their fishy sme…
B. As a result
-
question 30 of 39 determine the name or formula for each polyatomic ion…
carbonate ### For the name "nitrite ion":
-
motor oil would float on top of mineral oil densities of some common li…
False
-
give the systematic names of these compounds. spelling counts. cui(s): …
s: - $\ce{CuI(s)}$: copper(I) iodide - $\ce{Fe2O3(s)}$: iron(III) oxide - $\ce{CoF2(s)}$: cobalt(II) fluoride - $\ce{FeO(s)}$: iron(II) oxide
-
a scientist is conducting an investigation that involves water, silver,…
B. They are each made of matter. Some are compounds and some are elements. They all contain atoms.
-
time doth transfix the flourish set on youth and delves the parches in …
by personifying time as cruel and destructive
-
determine the formulas for these ionic compounds. copper(i) bromide: co…
$CuBr$ ### copper(I) oxide:
-
true or false? water is the only natural substance that is found in all…
A. true
-
question 27 of 39 what is the chemical formula for the compound formed …
For the compound between sodium and bromine: \(NaBr\) For the compound between sodium and selenium: \(Na_{2}Se\)
-
general chemistry 4th edition mcquarrie • rock • gallogly university sc…
- Metal: $\ce{Tl}$, $\ce{Ga}$, $\ce{Bi}$ - Semimetal (metalloid): $\ce{Sb}$, $\ce{Ge}$ - Nonmetal: $\ce{Se}$, $\ce{S}$
-
classify each compound as an ionic compound or a molecular compound. io…
Ionic compounds: AgI, BaO Molecular compounds: CS₂, CCl₄
-
which household activity is a significant source of volatile organic co…
using chemical - based cleaning products
-
for each element, identify the charge of its most common ion. i ○ +3 ○ …
s: - I: -1 - Rb: +1 - O: -2 - Al: +3
-
question 23 of 39 metals and nonmetals can react with each other to for…
- A potassium atom \(\boldsymbol{\text{loses}}\) \(\boldsymbol{\text{1 electron}}\) to form a \(\boldsymbol{\text{K}^+}\) (potassium) ion. - A sulfur atom \(\boldsymbol{\text{gain…
-
choose the correct answer. what is one of the characteristics of the tr…
B. high density of air molecules
-
why do garages usually have low air quality? they are outside. chemical…
B. Chemicals are stored in garages.
-
identify the missing information for each atom or ion. note that the at…
s: ### First Part: number of neutrons: \( \boldsymbol{43} \) number of protons: \( \boldsymbol{34} \) number of electrons: \( \boldsymbol{36} \) ### Second Part: element symbol: \…
-
how many protons are in an ion with 54 electrons and a −1 charge? numbe…
53 ### Second Sub - Question: How many total electrons are in a $\ce{Sr^{2+}}$ ion?
-
what is the charge on a hypothetical ion with 45 protons and 49 electro…
The charge on the ion is \(-4\) (or we can say the ion has a charge of \(4-\) as it has 4 more electrons than protons).
-
classify each compound by the number of chlorine atoms indicated in the…
- 1 Cl atom: $\ce{HClO2}$, $\ce{LiCl}$ - 2 Cl atoms: $\ce{BaCl2}$, $\ce{CCl2F2}$, $\ce{Ca(ClO3)2}$ - 3 Cl atoms: $\ce{Cr(ClO3)3}$ - 4 Cl atoms: $\ce{CCl4}$ - 5 Cl atoms: $\ce{PCl5…
-
section 2 short answer answer the following questions in the space prov…
Heterogeneous ### b. quartz
-
question 13 of 39 group the elements into pairs that would most likely …
Pair 1: Li, K Pair 2: F, Br Pair 3: S, O
-
identify these elements based on their locations in the periodic table.…
period 4, group 14 (4A): Ge period 5, group 12 (2B): Cd period 4, group 16 (6A): Se
-
antimony has two naturally occuring isotopes, (^{121}\text{sb}) and (^{…
\( ^{121}\text{Sb} \): \( \boldsymbol{57.19\%} \) \( ^{123}\text{Sb} \): \( \boldsymbol{42.81\%} \)
-
question 10 of 39 on another planet, the isotopes of titanium have the …
\(46.84\) (or more precisely \(46.8448\)) u
-
neon has three stable naturally occurring isotopes. the isotopic mass a…
The average atomic mass of neon is approximately \(\boldsymbol{20.18}\) u.
-
the half-life of iodine-131 is 8 days. how many milligrams of iodine-13…
A. 0.500 mg
-
question 29 of 30 the emission spectrum of hydrogen is shown below. wha…
B. Light with wavelengths of 410 nm, 434 nm, 486 nm, and 656 nm is given off when electrons fall to lower energy levels.
-
question 28 of 30 which quantum number represents the main energy level…
C. \( n \)
-
question 26 of 30 what are most likely the values of the quantum number…
A. \( l = 0; m_l = 0 \)
-
ralph claims that the author of a well-documented study on lead impacts…
a hasty generalization ### For Eloise's statement:
-
how many protons, neutrons, and electrons are there in a neutral atom o…
protons: 15 electrons: 15 neutrons: 15
-
the hydrogen emission spectrum is shown below. what is the energy of th…
A. \( 4.85 \times 10^{-19} \, \text{J} \)
-
identify the logical fallacy described in each example. ralph claims th…
ad hominem ### 2. Jenny's Claim
-
question 19 of 30 what is the value of the quantum number n for a spin-…
C. +2
-
which chemical reactions are not possible according to daltons atomic t…
The reactions that are not possible are $\boldsymbol{\ce{CCl4 -> CH4}}$ and $\boldsymbol{\ce{2H2 + O2 -> 2H2O + Au}}$. So the checkboxes for $\ce{CCl4 -> CH4}$ and $\ce{2H2 + O2 -…
-
5. all oxygen atoms have eight protons, and most have eight neutrons as…
The mass number is 17, and the isotope is oxygen - 17.
-
sulfur tetrafluoride, sf₄, has a mass ratio of sulfur to fluorine of 1.…
The chemical formula of the unknown compound is \( \boldsymbol{SF_6} \)
-
part 3 vocabulary-write out the correct numbers to complete the sequenc…
### Part 3 1. **Explanation**: - Step 1: Analizar la secuencia. "Vingt" (20), "vingt - quatre" (24). La diferencia es 4. Entonces el siguiente número es 24 + 4 = 28 ("vingt - huit…
-
question 2 of 39 element x forms three different compounds with element…
compound 2: \(XY_3\) compound 3: \(XY_2\)
-
in the combustion of hydrogen gas, hydrogen reacts with oxygen from the…
The mass of oxygen that reacted is \( 265.5\ \text{g} \)
-
periodic table worksheet instructions: using the periodic table fill ou…
To solve the periodic table worksheet, we use the following relationships for neutral atoms: - Atomic Number = Proton # = Electron # - Mass # (amu) = Proton # + Neutron # ### Row …
-
question 4 of 30 which of the following best describes an electron tran…
B. An electron gains or loses energy and moves between quantized energy levels.
-
question 1 of 30 a cobalt atom has 27 protons. what number of neutrons …
C. 32
-
determine the name for each of the ionic compounds from their formulas.…
s: - $\ce{Au2O3}$: Gold(III) Oxide (the system's marking as incorrect might be an error) - $\ce{NiPO4}$: If the formula is correct, Nickel(III) Phosphate; if the formula is $\ce{N…
-
question 28 of 30 what must happen for ice to melt at a given pressure?…
C. Thermal energy must be transferred to the ice from its surroundings.
-
question 27 of 30 at what temperatures is a reaction that has a positiv…
B. At all temperatures for exothermic reactions
-
question 26 of 30 which is characteristic of an exothermic reaction? a.…
C. Material releases heat to its surroundings.
-
question 4 of 24 write the nuclear symbol for the neutral atom shown. n…
\( \ce{_{12}^{24}Mg} \)
-
question 25 of 30 which statement best describes what happens when ther…
B. The thermal energy is spread out by the surrounding air.
-
what is the change in entropy (δ s) when an icicle melts at 2°c? a. δ s…
B. \(\Delta S>0\)
-
density = mass/volume what is the density of the object? mass = 51.842 …
\( 19.2\space g/mL \) (The unit is grams per milliliters as density is mass per unit volume, so the unit should be \( g/mL \))
-
question 22 of 30 which of the following choices fits in the blank to c…
D. $- T\Delta S^0$
-
determine the formula for each compound from its name. lithium oxalate:…
$Li_2C_2O_4$ ### 2. Iron(III) Oxide
-
the thermochemical equation for the reaction of carbon dioxide with sul…
B. It is endothermic.
-
question 19 of 30 at 298 k, $\\delta h^0 = 46$ kj/mol and $\\delta s^0 …
C. 17 kJ
-
question 18 of 30 what does a change in the entropy of a system indicat…
C. That the disorder of the system has changed
-
question 13 of 14 determine the name for each of the ionic compounds fr…
s: $\ce{CaS}$: calcium sulfide $\ce{Au_{2}O_{3}}$: gold(III) oxide $\ce{K_{2}CO_{3}}$: potassium carbonate $\ce{NiPO_{4}}$: nickel(III) phosphate
-
you need to calculate the enthalpy change ($\\triangle h^0$) of the rea…
A. \( \Delta H^{\circ} = \Delta H^{\circ}_2 - \Delta H^{\circ}_1 \)
-
what type of reaction occurs without the addition of heat? a. a spontan…
A. A spontaneous reaction
-
determine the number of electrons lost or gained when each atom forms a…
Be: loses 2 electrons. Se: gains 2 electrons. I: gains 1 electron. P: gains 3 electrons.
-
question 15 of 30 for a phase change, $\\triangle h^0 = 31$ kj/mol and …
C. \(\triangle G = 3.1\space kJ\); nonspontaneous
-
3. what is the difference between a coefficient and a subscript in a ch…
- Coefficient: A number placed before a chemical formula (e.g., \(2\) in \(2H_2O\)) to show the number of molecules/units of that substance. - Subscript: A number written below an…
-
select all the true statements. the cl⁻ and br⁻ ions have the same numb…
B. The $\ce{Fe^{2+}}$ and $\ce{Fe^{3+}}$ ions have the same number of protons. D. The $\ce{K^+}$ ion is formed when a potassium atom loses one electron.