Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
-
metals have the largest... atomic radius only ionization and atomic rad…
A. atomic radius only
-
which of the following will have a higher electronegativity than arseni…
B. Carbon (C)
-
experiment a pair of 100 ml samples of water are taken from a well bore…
### First Experiment (NaCl Precipitation)
-
12/35 ionization energy is .... a measure of the ability of an atom to …
C. how much energy it takes to remove an electron from an atom (assuming the options are labeled A, B, C, D with A being the first, B the second, C the third, D the fourth)
-
the element most chemically similar to chlorine is ___. options: na, i,…
I (Iodine)
-
as you move down a group, atomic radius increases because - you add mor…
A. you add more and more shells (energy levels)
-
which has the greater electronegativity; n or c? n c
N
-
properties of matter / states of matter 17. define physical change (ref…
A physical change is a change in a substance's form/appearance (e.g., state, size, shape) without altering its chemical composition (no new substance formed, e.g., melting ice, cu…
-
which of the following has a larger radius than zinc magnesium gallium …
Strontium (the option with "Strontium" text) has a larger radius than Zinc.
-
7/35 electronegativity is... how easy it is to make friends. the abilit…
C. the ability of an atom to attract/ accept electrons
-
the atom with the largest atomic radius in period 4 (row 4) is - fe k f…
B. K
-
vertical columns of elements (families) on the periodic table with simi…
D. groups
-
write the number of protons and draw dots for each electron in each of …
To solve for the number of protons and valence electrons (and draw electron dots) for each atom, we use the following principles: ### Step 1: Number of Protons The number of proto…
-
the atom with the largest atomic radius in period 4 (row 4) is - option…
The atom with the largest atomic radius in Period 4 is K (Potassium). Among the given options (assuming the first Fe is a duplicate and the options are Fe, Fe, Kr, K), the correct…
-
electronegativity is the ability of an atom to accept/ attract electron…
A. the ability of an atom to accept/ attract electrons
-
as you move across the periodic table, from left to right, ionization e…
increasing
-
the element with the smallest ionization energy in period 6 is - (optio…
B. Cs
-
5. why is mercury no longer used in many devices?
Mercury is toxic; improper disposal/release harms the environment (bioaccumulation, ecosystem damage) and human health (nervous system effects). Safer alternatives and regulations…
-
properties of matter / states of matter name: ladoinan panfort integrat…
To solve this, we identify physical and chemical changes. A physical change doesn't form new substances; a chemical change does. ### Physical Change (no new substance, just form/s…
-
16 question (2 points) an atom has an atomic symbol of ( ^{27}\text{al}…
13 ### Part 2
-
4. state one reason gold is used in jewelry.
One reason gold is used in jewelry is its high malleability (and ductility), allowing it to be shaped into intricate designs. (Or other valid reasons like its lustrous appearance,…
-
many choice question why can the p atom have more than four bonds, and …
C. It’s in N = 3, so it can use "d" orbitals
-
3. define ductility.
Ductility is the property of a material (typically metals) to undergo plastic deformation (be stretched, drawn, or deformed without breaking) under tensile stress, often measured …
-
2 multiple choice 1 point nutrients circulate endlessly throughout the …
C. biogeochemical cycles
-
1. what properties of an element are affected by electron 2. define mal…
Malleability is the ability of a material (especially a metal) to be hammered, rolled, or pressed into thin sheets without breaking or cracking, involving plastic deformation unde…
-
when sodium reacts with chlorine, a chemical change occurs forming salt…
D. Chlorine is a gas at room temperature. Salt is a solid. The product of the change has new properties.
-
16. choose all that apply. which three are lab rules? □ use hand signal…
- No food or drink is allowed. - Clean up after the experiment. - No horseplay is allowed.
-
use hand signals instead of verbal communication.. no food or drink is …
The incorrect rule is: Store all chemicals in a plastic bucket.
-
this safety symbol tells you what to use if ______. image: green square…
C. you get chemicals in your eyes or on your skin (assuming the options are labeled A, B, C, D with C being "you get chemicals in your eyes or on your skin")
-
question 5 (1 point) saved listen n-15 is an ???? of nitrogen and has ?…
B) Isotope; 8
-
question 4 (1 point) saved listen a ph of 5 is ________ times more ____…
A) 1000; acidic
-
convert 0.0998 liters to milliliters. 0.000098 ml 99.8 ml 9.98 ml 998 ml
99.8 mL (the option: 99.8 mL)
-
what do these two changes have in common? dew appearing on grass in the…
- Both conserve mass. - Both are only physical changes.
-
what do these two changes have in common? salt and vinegar removing tar…
Both conserve mass, Both are chemical changes
-
based on the bond energies for the reaction below, what is the enthalpy…
\(\boxed{-1222}\)
-
a substance is placed in a closed vessel. the substance is continuously…
- Region 1: Diagram 2 - Region 2: Diagram 1 - Region 3: Diagram 5 - Region 4: Diagram 3 - Region 5: Diagram 4 (Note: The specific matching depends on the particle arrangements: so…
-
for a reaction where $\\delta h^\\circ = +573\\ \\text{kj/mol}$ and $\\…
The reaction occurs spontaneously at temperatures greater than \(\boldsymbol{\approx 349\space K}\) (the transition temperature is approximately \(349\space K\)). If we calculate …
-
entropy increases when the degrees of freedom increases. usually, if th…
B. \(\Delta S\) is (-)
-
a substance is placed in a closed vessel. the substance is continuously…
(Assuming the Diagrams): - Third diagram ("Tap Me!") → Region 2 (melting, solid + liquid coexist) - Fifth diagram ("Tap Me!") → Region 4 (boiling, liquid + gas coexist) (Note: The…
-
what do these two changes have in common? adding dish soap to water in …
A. Both conserve mass B. Both are chemical changes
-
given $\\delta h^\\circ = +90.7\\ \\text{kj/mol}$ and $\\delta s^\\circ…
\(24.8 \text{ kJ/mol}\)
-
classification of matter directions: unscramble the terms in each of th…
heterogeneous ### Question 2
-
most of your cooking equipment is copper and your utensils are silver. …
Iodine - based
-
a substance is placed in a closed vessel. the substance is continuously…
To solve this, we analyze the heating curve and particle representations (states of matter: solid, liquid, gas; and phase changes: melting, boiling): ### Step 1: Identify Regions …
-
food surfaces and equipment are not fully cleaned and sanitized until? …
They have been treated with heat or chemicals.
-
what do these two changes have in common? sauce burning on a stove cell…
Both are chemical changes. Both conserve mass.
-
what do these two changes have in common? melting wax water evaporating…
A. Both are only physical changes, C. Both are caused by heating
-
content mastery matter directions: complete the paragraphs using the te…
1. physical change 2. mixture 3. liquid 4. physical properties 5. physical change 6. chemical change 7. melting 8. equals 9. conservation of mass 10. difference (in) 11. distillat…
-
what do these two changes have in common? shaking up salad dressing sno…
- Both conserve mass. - Both are only physical changes.
-
what do these two changes have in common? milk going sour newly poured …
- Both conserve mass. - Both are chemical changes.
-
sanitization can be accomplished by all of the following means except: …
Air drying
-
what do these two changes have in common? dust settling out of the air …
Only the option "Both are only physical changes" is correct. So the correct option is: Both are only physical changes.
-
a mixture can be: a either homogeneous or heterogeneous b element or co…
A. Either homogeneous or heterogeneous
-
consider the same reaction: 1 molecule of nitrogen (n₂) reacts with 1 m…
2
-
which of the following is a pure substance? a distilled water b granite…
A. Distilled Water
-
in the atmosphere, nitric oxide forms when a lightning strike causes ni…
For N: \( 2 \) For O: \( 2 \)
-
which of the following is not an element? a water (h₂o) b gold (au) c o…
A. Water ($H_2O$)
-
in which state of matter do particles move the fastest? a gas b liquid …
A. Gas
-
sulfur dioxide is a gas released when volcanoes erupt. it can react wit…
### Part 1: Completing the table (Atoms Conservation) #### For Oxygen (O) atoms: - In $\ce{SO_2}$: Each $\ce{SO_2}$ has 2 O atoms. 12 molecules of $\ce{SO_2}$ have $12\times2 = 24…
-
a temperature vs. time graph with y - axis labeled temperature (°c) and…
To solve this problem, we analyze the temperature - time graph (a cooling curve, as temperature decreases over time) and match each segment to the correct state or phase change: #…
-
which of these is a compound? a salt (nacl) b gold (au) c helium (he) d…
A. Salt (NaCl)
-
a homogenous mixture is best described as: a a pure element b a solid a…
C. A mixture that looks the same throughout
-
hydrogen peroxide can be used to disinfect and clean surfaces around th…
s: - H atoms: 12 - O atoms: 12 - $H_2O_2$ molecules: 6
-
gases take the volume of their container. f false t true
T. True
-
directions: choose the correct category from the list for each item. ea…
b. compound ### Question 2
-
sulfuryl chloride is a substance used to make chemicals for killing ins…
s: - O atoms: \( \boldsymbol{4} \) - S atoms: \( \boldsymbol{2} \) - Cl atoms: \( \boldsymbol{4} \) - Molecules of \( SO_2Cl_2 \): \( \boldsymbol{2} \)
-
which of these is a homogeneous mixture? a air b salad c sand d granite
A. Air
-
ethanol is a chemical that is used in many hand sanitizers. it is produ…
s: - H atoms: $\boldsymbol{36}$ - C atoms: $\boldsymbol{12}$ - O atoms: $\boldsymbol{6}$ - Ethanol molecules: $\boldsymbol{6}$
-
when you burn a candle, all that remains is a puddle of wax. the puddle…
A. changed to gases
-
directions: complete the concept map using the terms in the list below …
s: #### Concept Map: 1. substances 2. elements 3. compound 4. mixtures 5. homogeneous 6. heterogeneous #### Questions 7–10: 7. invisible; can 8. physical 9. chemical 10. conserved
-
a heterogeneous mixture has the same composition throughout. t true f f…
F. False
-
rocket engines can be fueled by liquid hydrogen. the liquid hydrogen re…
s: - Number of H atoms: \( \boldsymbol{8} \) - Number of O atoms: \( \boldsymbol{4} \) - Molecules of \( H_2O \): \( \boldsymbol{4} \)
-
according to the law of conservation of matter, which of the following …
A. Matter can rearrange particles into different substances, B. Matter can change to another state of matter
-
hydrogen chloride is often used to help make a material found in plasti…
s: - Number of H atoms: \( \boldsymbol{4} \) - Number of Cl atoms: \( \boldsymbol{4} \) - Number of HCl molecules: \( \boldsymbol{4} \)
-
a substance is placed in a closed vessel. the substance is continuously…
2, 4
-
a substance is placed in a closed vessel. the substance is continuously…
Region 5
-
a substance is placed in a closed vessel. the substance is continuously…
1, 3, 5
-
phase diagram pressure / atm temperature / °c part c what is the pressu…
D. 0.6 atm ### Part D
-
phase diagram 3.0 2.0 pressure / atm 1.0 0.0 0 25 75 125 temperature / …
C. 100 C ### Part B
-
identify the names of the state changes depicted in the diagram. tap th…
1. Sublimation 2. Deposition 3. Melting 4. Freezing 5. Evaporation (or Boiling) 6. Condensation
-
which of these is a pure substance? a iron (fe) b salt water c salad d …
A. Iron (Fe)
-
select the correct answer. lars observes a substance to be a solid and …
B. cetyl alcohol
-
auto saved at: 11:34:14 for parts of the free - response question early…
The type of chemical bond present in the $\ce{Cl_{2}}$ molecule is a non - polar covalent bond (or covalent bond). ### Part (b)
-
phase changes heating curve of substance x (graph with temperature (°c)…
E. I ### Part B
-
drag each tile to the correct box. arrange the sublevels in ascending o…
s sublevel < p sublevel < d sublevel < f sublevel
-
select all the correct answers. properties of substances can be classif…
C. Silver tarnishes and becomes black when exposed to oxygen, E. Diesel fuel burns when it is heated
-
select the correct answer. justin mixed two clear liquids together duri…
B. A chemical change occurred, and this caused the liquid’s physical properties to change.
-
select the correct answer. which tool is most suitable for a chemist to…
A. electronic balance
-
select all the correct images. which images show a container holding a …
The bowl of soup (top - left) and the jar of coins (bottom - right) are the correct images showing a container holding a heterogeneous mixture.
-
phase diagram pressure (atmospheres) 2.00 1.75 1.50 1.25 1.00 0.75 0.50…
C. Gas ### Part D (Freezing point at STP)
-
question 5 (1 point) after heating your sample, you should remove your …
False
-
valence electrons are found in the blank energy level and determine how…
First blank: outermost; Second blank: interact
-
question 4 (1 point) which of the following two compounds could be your…
A) \( \text{CaSO}_4 \cdot 2\text{H}_2\text{O} \)
-
phase diagram pressure (atmospheres) 2.00 1.75 1.50 1.25 1.00 0.75 0.50…
C. Sublimation ### Part B
-
drag each tile to the correct location. which type of change does the s…
- **Physical Change**: - There is no change in the chemical properties of the substance. - Particles retain their composition and identity. - **Chemical Change**: - Particles rear…
-
drag and drop the words into the correct locations. (1 point) metals ar…
First blank: left; Second blank: lose
-
select the correct answer. zoe is investigating the composition of subs…
A. a compound
-
question 3 (1 point) what is the percent mass of water in the hydrated …
A) 26.52%
-
nitrogen is an organic molecule that has an atomic mass of ▼. nitrogen …
- Atomic mass of nitrogen: 14.007 - Nitrogen has 7 protons - Nitrogen has 7 electrons
-
drag each label to the correct location on the image. match the subatom…
- Central red sphere (nucleus): proton, neutron - Electron shells (dashed circle and other orbits): electron