Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
-
14. 2500 grams of 1-propanol solution was used in a calorimeter as the …
The specific heat capacity of 1 - propanol is \( 2.3 \) kJ/kg\(^\circ\)C.
-
question 3 what is the term referred to when fathers or significant oth…
A. Bonding
-
*53. classify the following materials as an element, compound, or mixtu…
Compound. Reason: NaCl is made of two different elements (Na and Cl) chemically bonded in a fixed ratio. ### Part b: Salt water
-
fill in the blank question one or more substances dissolved in another …
solution
-
2.3 elements and compounds 52. how could you distinguish an element fro…
To distinguish an element from a compound: 1. **Chemical Decomposition**: An element cannot be broken down into simpler substances by chemical reactions (it is the simplest form o…
-
multiple choice question a substance that reduces the proton concentrat…
B. base
-
fill in the blank question a substance found in lesser quantity that di…
solute
-
fill in the blank question hydrochloric acid (hcl) and sulfuric acid (h…
hydrogen (\(H^+\))
-
multiple choice question what property of water causes water to bead to…
Cohesion (the option labeled "Cohesion")
-
multiple choice question when an atom either gains or loses electrons, …
an ion
-
multiple choice question in the picture, a carbon atom is joined to fou…
covalent
-
multiple choice question to make lemonade, water is combined with lemon…
A. Water is the solvent
-
multiple choice question the relatively strong attractive force that ho…
B. a chemical bond
-
fill in the blank question 8 of 29 concepts completed water has cohesiv…
hydrogen
-
multiple choice question there are two types of subatomic particle loca…
The neutron
-
fill in the blank question if a substance cannot be broken down by chem…
element
-
fill in the blank question when sodium chloride (nacl) is dissolved in …
ions
-
multiple choice question a cat, a turtle, a human, and a book all have …
B. They are all considered matter (assuming the options are labeled A, B, C as: A. They are all examples of molecules, B. They are all considered matter, C. They all can do work o…
-
multiple choice question what type of bond involves two or more atoms s…
D. covalent bond
-
fill in the blank question chemical bonds such as the covalent bond hol…
First blank: atoms; Second blank: molecules (or compounds)
-
fill in the blank question atoms with the same number of protons belong…
element
-
multiple choice question atoms are extremely small particles and are co…
B. protons, neutrons, and electrons.
-
multiple choice question when two or more atoms are chemically joined, …
D. molecule
-
multiple choice question all matter is composed of ______, which are th…
C. atoms
-
3) the complete photoelectron spectrum for an element is shown. what ox…
c) \( \boldsymbol{XO} \)
-
you do: 1) which of the following has the same number of electrons as c…
d) \( \text{K}^+ \)
-
we do: element 117 was recently discovered and is named tennessine. ass…
Noble gas electron configuration: \(\boldsymbol{[Rn]7s^25f^{14}6d^{10}7p^5}\); Ionic compound formula: \(\boldsymbol{MgTs_2}\)
-
question 22 - 1 point sheena’s multivitamin contains 1100 mg of potassi…
\(1.1\)
-
2. how many cu atoms are there in 7.55 g cu? cu=63.55g 7.55×2 +63.55=78…
Approximately $7.15 \times 10^{22}$ Cu atoms.
-
solid liquid gas plasma 1. a __________ does not have a definite shape …
Gas #### 2.
-
if a chemical splashes in the eyes, the eyes should be flushed in an ey…
d. For 15 minutes.
-
based on the molecules below, indicate whether each of the following st…
False ### 2. Second Statement:
-
in the image below, which of the following correctly indicates shared e…
The correct option is the bottom - most choice (with \( \delta^- \) on N, \( \delta^+ \) on H - N, \( \delta^- \) on O, \( \delta^+ \) on H - O, and \( \delta^+ \) on C in \( C = …
-
name: ... class ... date ... use the words and phrases to complete the …
B. Molecule #### Question 2:
-
what type of control would describe training, inspection, and housekeep…
Administrative
-
what are the potential chemical hazards of a sprayed paint mist in a wo…
A. Inhalation, B. Absorption
-
1 complete the following table. | isotopic symbol (nuclear form) | isot…
To solve the isotope table, we use the following relationships: - Atomic number (\(Z\)) = Number of protons = Number of electrons (in neutral atoms). - Mass number (\(A\)) = Numbe…
-
9 in what way are atoms similar to building blocks? a they can only be …
D. They combine to form different structures
-
8 what evidence supports the idea that seawater is a homogeneous mixtur…
C. It tastes just as salty throughout the entire mixture
-
7 what is the relationship between atoms and elements? a atoms are simp…
B. Atoms are the basic units of elements
-
6 what is the similarity between a compound and a mixture? a they conta…
A. They contain more than one element
-
5 why is water both a compound and a pure substance? a it is made of al…
B. It is made of all the same kind of molecules, but each molecule contains more than one type of atoms
-
4 classify each statement based on the type of mixture it describes. pa…
To solve this, we recall the definitions of heterogeneous and homogeneous mixtures: - **Heterogeneous Mixture**: Components are not evenly distributed (visible differences, variab…
-
3 match each word with its description. rearrange matter form bond prop…
- All substances: Matter - Create: Form - Connect: Bond - Move around: Rearrange - Characteristic: Property
-
2 what is an effect of a chemical reaction? choose three. alteration of…
- Alteration of chemical bonds - Formation of a new substance with different properties - Change in chemical properties
-
1 which ingredients can combine to form a compound? choose two. table s…
B. Carbon, F. Oxygen
-
model 2 – results of alka-seltzer® experiment trial | number of alka-se…
Trial 5
-
problem 2-9 which of the following pairs of structures represent resona…
### Problem 2 - 9 #### Part (a) # Brief Explanations: Resonance forms differ only in the distribution of electrons (π electrons or lone pairs), not in the position of atoms. In th…
-
model 2 – results of alka-seltzer® experiment | | trial 1 | trial 2 | t…
Trial 5 ### Question 6a
-
a orbital by definition is a the path on which the electron resides b t…
C. the space around the nucleus where the probability of finding the electron will be maximum
-
all four quantum numbers for any electron can be same or different
False
-
as you move away from the nucleus, the energy of an electron increases
True
-
for n=2, the total number of subshells possible are a 2 b 1 c 0 d data …
A. 2
-
for n=2, total number of orbitals are a 3 b 2 c 1 d 4
D. 4
-
any orbital can hold a maximum of ____ electrons a 1 b 2 c 3 d any amou…
B. 2
-
a flask contains 0.410 mol of liquid bromine, br₂. determine the number…
\( 2.47\times10^{23} \) (or more precisely \( 2.46902\times10^{23} \)) molecules
-
which orbital and electron can be designated for n=3, l=1, m=-1, s=-1/2…
D. 3py, spinning anti - clockwise
-
at a ph of 7, which of the following would be true? multiple choice h⁺ …
A. \(\ce{H+}\) and \(\ce{OH-}\) concentrations would be equal.
-
what is the term for a substance that causes a resistance to a change m…
C. Buffer
-
there are ______ naturally occurring elements of which ______ are invol…
D. 92; 24 (assuming the last option is labeled D, with the text "92; 24")
-
which of the following is an organic molecule? multiple choice naoh c₆h…
B. \( \boldsymbol{\text{C}_6\text{H}_{12}\text{O}_6} \) (assuming the options are labeled A: \( \text{NaOH} \), B: \( \text{C}_6\text{H}_{12}\text{O}_6 \), C: \( \text{NaHCO}_3 \)…
-
which term describes a solution that contains more hydroxide ions than …
D. Basic
-
water molecules are special. but what makes them so special? multiple c…
C. The bend in their structure (assuming the options are labeled A, B, C, D with A: Because they are liquid, B: Polar bonds, C: The bend in their structure, D: Their abundance)
-
the process used to convert liquid vegetable oils to solids by changing…
B. hydrogenation (assuming the second option is labeled B; if the original labels were different, adjust the identifier, but the text is "hydrogenation")
-
indicate whether each statement is true or false. 1. the ph scale is a …
False ### 2.
-
as hydrogen ion concentration increases, the ph number ________. multip…
C. decreases (assuming the options are labeled A: increases, B: becomes negative, C: decreases, D: stays the same)
-
how does a buffer help a solution maintain ph? multiple choice a buffer…
D. A buffer can act like a base if pH is acidic, and it can act like an acid if pH is basic. (Note: Assuming the last option is D as it's the fourth option. If the options were la…
-
which of the following is an organic molecule? multiple choice salt (na…
B. Sucrose ($\ce{C_{12}H_{22}O_{11}}$)
-
a solution that contains more hydrogen ions (h⁺) than hydroxide ions (o…
acidic (or acid)
-
why? working in the science lab can be a lot of fun. mixing random chem…
Alka - Seltzer is added to 100.0 mL of vinegar (at 23.5 °C and 84 kPa); a reaction occurs with gas (bubbles) production, and after the reaction, a 100.0 mL solution is formed at 2…
-
check all of the following that are characteristics of buffers. check a…
- $\boldsymbol{\square}$ Can pick up excess $\ce{H+}$ (should be checked) - $\boldsymbol{\square}$ Can release $\ce{H+}$ when $\ce{H+}$ is lacking (should be checked) - $\boldsymb…
-
ter 2 exam, substances that do not contain carbon are ______ substances…
B. inorganic; organic
-
based on this information, which type of bond is stronger — a covalent …
A covalent bond is stronger. Covalent bonds are intramolecular (within a molecule, e.g., O - H in $\ce{H_2O}$) and involve electron - sharing to hold atoms together. Hydrogen bond…
-
multiple choice question how do the number of valence electrons and the…
D. same valence electrons, different number of energy levels (assuming the last option is labeled D; if the original options had labels like A, B, C, D with the last one being "sa…
-
which gas forms 21% of earths atmosphere? a. argon b. carbon dioxide c.…
D. oxygen
-
lets quickly review the differences between covalent bonds and hydrogen…
### Covalent Bond: - holds the atoms in a single water molecule together - formed when two atoms share electrons ### Hydrogen Bond: - formed from an attraction between a partial p…
-
the number of in an atoms nucleus is equal to its atomic number.
protons
-
true or false question true or false: atomic mass does not always incre…
True
-
ionization energy is the energy required to remove an electron from an …
According to Coulomb’s Law (\( F = k\frac{q_1q_2}{r^2} \)), the force (\( F \)) between the nucleus (positive charge, \( q_1 \)) and the outermost electron (negative charge, \( q_…
-
in the modern periodic table, elements are arranged by increasing . nee…
atomic number (or proton number)
-
____, ____, and ____ are the three basic subatomic particles that make …
Protons, Neutrons, Electrons
-
which is the weighted average mass of all naturally occurring isotopes …
B. average atomic mass
-
for atoms to be different isotopes of an element, they must have differ…
B. neutrons
-
what is the term for the small, positively charged center of an atom? ○…
A. nucleus
-
a(n) is the smallest particle of an element that retains the element’s …
atom
-
4. give five examples of chemical transformations (changes) that you ma…
1. Burning of Wood (Campfire) - New substances (CO₂, ash) formed. 2. Rusting of Iron (Bicycle Chain) - Iron oxide (rust) formed. 3. Cooking an Egg - Protein denaturation, new stru…
-
adding a proton to the nucleus of an atom (or removing one), and an ele…
element
-
unit examinations content page 26 of 51 question 25 which abbreviation …
B. CHF—cardiogenic heart failure
-
(1 of 10) a 4.0 molar solution of glucose (c₆h₁₂o₆) would have an osmol…
an osmolarity of 4.0
-
fred has been having severe memory difficulties of late, and his doctor…
A. PET
-
lab questions 1. does a substance have to be water soluble to be classi…
No ### Question 2 #### Ionic
-
the atomic weight of nitrogen is very near 14, indicating that most nit…
B. 7
-
click to fix any capitalization errors below. click \submit answer\ if …
Whenever Luca Paguro's chemistry teacher sat in the dunking booth at the school's Spring Fling, ticket sales were huge.
-
ch 2 chemistry reading quiz - chapter 2 question 5 part a ______ is an …
C. Carbon dioxide
-
read each question. follow the instructions to answer the questions. 1.…
C. a combination of substances that keep their own properties ### Question 2
-
part a which element do organic compounds always contain? ○ n ○ c ○ h ○…
B. C
-
reading quiz - chapter 2 question 7 part a if a solution has a ph that …
A. acidic
-
part a a solution containing more hydrogen ions than hydroxide ions is …
D. acidic (assuming the options are labeled as A. neutral, B. in equilibrium, C. basic, D. acidic)
-
when would it be most appropriate to use chemical sterilization? ○ for …
C. For instruments that are sensitive to heat and steam
-
multiple choice question chemical sterilization is also known as ______…
B. cold