化学
化学反応、化学量論、分子構造、元素の性質。
-
1. $c_3h_8 + 5o_2 \ ightarrow 3co_2 + 4h_2o$ a. if i start with 5 moles…
a. $20$ moles b. $4$ moles c. $\text{O}_2$ (oxygen) d. $4$ moles of $\text{H}_2\text{O}$
-
select all the statements that are true of the physical aspects of soun…
- Air molecules move in regular, wavelike patterns. - A medium such as air or water is necessary to conduct sound to our ears. - It is created by a vibrating source.
-
2. what three deductions are taken from everyones pay? a. b. c.
a. Income Tax b. Social Security (or national pension scheme contributions) c. Medicare (or public health insurance contributions)
-
given the (unbalanced) reaction equation: nh₃(g) + o₂(g) → no(g) + h₂o(…
- First reaction: $-902$ kJ - Second reaction: $-1266$ kJ
-
select all the statements that are true of the physical aspects of soun…
- Air molecules move in regular, wavelike patterns. - A medium such as air or water is necessary to conduct sound to our ears. - It is created by a vibrating source.
-
which of the following be the correct lewis structure for cacl₂? a. :cl…
C. $[:\ddot{\text{Cl}}:]^- \text{Ca}^{2+} [: \ddot{\text{Cl}}:]^-$
-
indicate whether each electron configuration below is correct or incorr…
1. $\text{S}^{2-}$: Incorrect 2. $\text{Rb}^{2+}$: Incorrect 3. $\text{Ga}^{3+}$: Incorrect
-
8. read the passage below. which of the following best describes the au…
8. A. to persuade and to inform 9. C. to inform and to entertain
-
indicate whether each electron configuration below is correct or incorr…
1. $\text{K}^+$: Incorrect 2. $\text{Ni}^{2+}$: Incorrect 3. $\text{As}^{3-}$: Correct 4. $\text{Cu}^{2+}$: Incorrect 5. $\text{Br}^{2-}$: Incorrect 6. $\text{Fe}^{3+}$: Correct
-
advanced practice - homework which of these atoms has the smallest numb…
A. \(^1\text{H}\) ### Q4 (Which one of the following is a correct electron arrangement?)
-
multiple choice question if your specific purpose is \to persuade my au…
a reason why listeners should only eat organic produce
-
q8.an atom in which the number of protons is greater than the number of…
C. \(^3\text{He}\) ### Q10
-
directions: answer each question completely. indicate how you determine…
$KClO_3 ightarrow KCl + O_2$ ### Part b
-
reduction is the gain of electrons. true false
A. True
-
1. define polar covalent bond. 2. define non - polar covalent bond. 3. …
A covalent bond where electrons are shared unequally between atoms (due to different electronegativities), creating partial charges (δ⁺ and δ⁻) on the atoms. ### Question 2: Defin…
-
when nacl (table salt) forms, sodium (na) loses energy by ______ and ch…
A. giving up an electron in oxidation; gaining an electron in reduction
-
oxidation-reduction reactions never occur at the same time. remove elec…
occur simultaneously.
-
sea caves in cape greco national forest park, cyprus which type of weat…
A. mechanical weathering
-
the chemical formula for glucose is ______. \\(\\boldsymbol{\\mathrm{c_…
The fifth option (the one with \( C_6H_{12}O_6 \))
-
which of the following is not an example of kinetic energy? heat light …
the energy in chemical bonds
-
the amount of energy required to raise the temperature of one gram of w…
A. calorie.
-
a ______ is the amount of energy required to raise 1 gram of water 1 de…
calorie
-
a measure of the degree of disorder in a system is called _______. ente…
entropy
-
what are the building principles of an organic management system? - int…
A. Interdependency and cooperative effort ### Question 20 (False Statement about Larger Organizations)
-
elements of the periodic table 13. which element is number 16 on the pe…
s: 13. Sulfur 14. Na 15. 30 16. ~12.01 (or 12) 17. Tungsten 18. 37 19. 15 20. Xenon 21. Neptunium 22. 83
-
elements of the periodic table 1. what is an element? a basic part of a…
To answer the blanks in the "Elements of the Periodic Table" web quest: ### Question 2: Currently, **94** different elements are known to exist in nature, although additional elem…
-
page 4-history of canada______ (5 pts) canadian shield -- what are the …
1. Gold 2. Silver 3. Copper
-
a solution made from betacarotene is orange in color. what wavelength r…
450 - 480 nm
-
forensic analysis a forensic chemist intern is trying to determine info…
Use a more dilute unknown sample to change the amount of dye interacting with the light.
-
yellow 5 dye determining concentration the calibration curve for a set …
3.25 x 10⁻⁴ M
-
anthocyanin experiment choosing the experimental wavelength consider th…
540 nm
-
color and wavelengthinterpreting absorbance vs λa visibly green-colored…
One molecule that reflects the color green.
-
what is the main goal of determining the relative age of a rock? to fin…
To determine if a rock is older or younger than another rock
-
anthocyanin experiment determining concentration anthocyanins are red o…
C. $3.1 \times 10^{-4}$ M
-
experimental adjustment using the beer-lambert law determination of per…
Diluting the unknown sample, as the unknown sample concentration is too high.
-
green dye experiment determining concentration the calibration curve is…
0.0065 M (matches option: 0.0065 M)
-
5. in which of the following liquids do the intermolecular forces inclu…
5. (D) $\text{CH}_2\text{F}_2(l)$ 6. (D) $\text{CCl}_4$ 7. (C) $\text{CO}_2$ 8. (C) $120^\circ$
-
synthetic fibers, such as nylon, are made of long-chain monomers. multi…
polymers.
-
methyl alcohol is the common name for methane. methanol. ethanol. ether.
methanol.
-
question 17 (5 points)listenwhich of the following is a formula for a h…
D. $\text{CH}_4$
-
Question was provided via image upload.
(D) Hexane molecules have electron clouds that are larger than those of methanol molecules. --- ### Question 4
-
listen the following are molecular formulas. which formula represents a…
Propene ($C_3H_6$)
-
question 13 (5 points)listenwhat is the defining quality of an organic …
It must contain carbon.
-
1. in the diagram above, which of the labeled arrows identifies hydroge…
1. (D) D 2. (A) $\text{Zn}^{2+} > \text{Ca}^{2+} > \text{Ba}^{2+}$ because the smaller ions have a stronger coulombic attraction to water
-
the effects of the maillard reaction are not just about color, however.…
The Maillard reaction is a chemical reaction that occurs between acids and sugars, causing foods to brown and gain a rich flavor. This process enhances the smell and taste of cert…
-
what is represented by the number below the abbreviation of the element…
A. The atomic mass
-
which of the following elements is among the alkali metals?○ magnesium …
Potassium (K)
-
what name is given to the elements that appear in the right-most column…
Noble gases
-
an atom that becomes positively charged due to the loss of one or more …
cation.
-
question 9 (5 points)listenwhat product is formed by a reaction in whic…
D. A salt
-
which of the following is a general characteristic of nonmetals rather …
In combination with hydrogen or with hydrogen and oxygen, they all form acids.
-
what is the balanced chemical equation for this reaction? $ce{h3po4 + h…
$\text{H}_3\text{PO}_4 + 5\text{HCl} ightarrow \text{PCl}_5 + 4\text{H}_2\text{O}$ (the second option)
-
according to the law of conservation of matter, how must a chemical equ…
D. An equal number of atoms must be on both sides of the equation.
-
an atom of oxygen has six electrons in its outermost ring and requires …
-2
-
listen if all the atoms in a molecule of a substance are alike, then th…
element.
-
listen what happens when a mixture is formed? two elements are mingled …
Two elements are mingled together without combining chemically.
-
which of the following is the best description of a gaseous substance?i…
It has no definite shape or volume and will expand indefinitely.
-
which model is the most likely to result in ionization? $h \ ightarrow …
The rightmost model (UV radiation interacting with the electron in the outermost orbital)
-
which of the following statements regarding absorption and emission spe…
C. Absorption and emission spectra are mirror images of each other for a particular chemical species.
-
london hooks feb 9, 2026 write a scientific explanation for the investi…
**Scientific Explanation:** Maya and Diego’s investigation into sugar dissolving in water tests key factors that govern the dissolution process through core solution chemistry pri…
-
a chemist adds 325.0 ml of a 1.14 m potassium iodide (ki) solution to a…
61.5 g
-
calculate the volume in milliliters of a 0.42 m barium chlorate solutio…
$2.0\times10^2$ mL
-
name: ____________ date: 2/9/26 per: 5 stoichiometry practice 2 - mass …
Approximately 41.3 grams of potassium oxide will be formed.
-
a chemist adds 195.0 ml of a $8.14 \\times 10^{-6}$ mol/l zinc oxalate …
$1.59$ μ mol
-
try again your answer is incorrect. you should keep your answer in scie…
$2.9 \times 10^2$ mL
-
calculate the volume in milliliters of a 0.77 mol/l iron(ii) bromide so…
290 mL
-
a student has two unopened 33 cl cans containing carbonated water. can …
B. Can B will make a louder and stronger fizz than can A.
-
predict what will be observed in each experiment below. experiment a pa…
The same mass of NaCl precipitate will form in Sample #2.
-
two 250 ml samples of water are drawn from a deep well bored into a lar…
A smaller mass of NaCl precipitate will form in Sample #2.
-
your answer is incorrect. predict what will be observed in each experim…
The bubbles will grow, and more may appear.
-
a chemistry student needs 60.0 g of 2-methylpyrazine for an experiment.…
228 g
-
a chemistry student needs 15.0 g of 2-ethyltoluene for an experiment. s…
117 g
-
question 10 (5 points)listenwhich of the following statements is accura…
D) The wavelength of both transverse and longitudinal waves is measured parallel to the direction of the travel of the wave.
-
name: kumardatesticky surfacesas you have learned in your friction expl…
1. **Graph Title**: Coefficient of Friction for Different Material Combinations 2. **X-axis**: Labeled "Material Combination", with categories: Ice-Wood, Ice-Steel, Leather-Wood, …
-
what is soil?soil is more than just dirt! its a mix of minerals, organi…
1. Minerals, organic matter (dead plants/animals), air, water, and living organisms 2. Topsoil (A Horizon) because it is a dark, nutrient-rich layer with lots of organic matter, m…
-
percent yield for the production of chalk labbackground:calcium carbona…
Percent yield of chalk (calcium carbonate): $\approx 76.0\%$ Actual mass of chalk: $1.80\ \text{g}$ Theoretical yield of chalk: $2.37\ \text{g}$ ### Filled Observations (expected)…
-
please type in the appropriate word in the blank to complete the paragr…
A. The element **symbols** which are represented by a single uppercase letter, or represented by an uppercase letter followed by a lowercase letter. This tells you the types of el…
-
pre-lab: what is the formula that is used to calculate the amount of he…
$\approx 4.78$ Food Calories
-
pre-lab: what is the formula that is used to calculate the amount of he…
1. The correct formula for heat absorbed/released by water during temperature change is $q = mc\Delta T$ (the provided $q=mHf$ is for phase change, not temperature change) 2. $\ap…
-
warm up question: how many atoms of each element are in the reactant (l…
### Reactants (left side): - Phosphorus (P): 4 atoms - Oxygen (O): 16 atoms - Hydrogen (H): 12 atoms ### Products (right side): - Phosphorus (P): 4 atoms - Oxygen (O): 16 atoms - …
-
a corn syrup sample has a density of 1.43 grams per milliliter at 25°c.…
Floats in the corn syrup sample: foam lid, six-sided die, wooden bead Sinks in the corn syrup sample: gold ring
-
journii birds practice d.1 calculate density, mass, and volume get 4 co…
420 grams
-
use the naming conventions and table of polyatomic ions to complete the…
1. Acid name: chromic acid; Chemical formula: $\ce{H2CrO4}$ 2. Acid name: boric acid; Chemical formula: $\ce{H3BO3}$ 3. Acid name: ascorbic acid; Chemical formula: $\ce{HC6H7O6}$ …
-
1) a gold necklace has a density of 18 grams per cubic centimeter and a…
27 grams
-
use the naming conventions to complete the following formula-name pairs…
1. Acid name: hydrotelluric acid; Chemical formula: $\text{H}_2\text{Te}$ 2. Acid name: hydrofluoric acid; Chemical formula: HF 3. Acid name: hydroiodic acid; Chemical formula: $\…
-
directions: how many grams are in the following elements and compounds?…
1. $96.21\ \text{g}$ 2. $32.68\ \text{g}$ 3. $498.48\ \text{g}$ 4. $174.77\ \text{g}$ 5. $34.01\ \text{g}$ 6. $8.29\ \text{g}$ 7. $87.12\ \text{g}$ 8. $89.12\ \text{g}$ 9. $143.70…
-
unit 6 quiz: stoichiometry using the balanced equation and reference in…
1. $1.36 \times 10^{24}$ molecules of $\text{CO}_2$ 2. $23.2$ liters of $\text{H}_2\text{O}$
-
the picture on the right the picture of the left which picture shows ma…
The picture on the right
-
4. how many moles of carbon dioxide ($co_2$) will be produced from 3.01…
4. $4.529$ moles of $\ce{CO2}$ (rounded to 4 significant figures) 5. The missing conversion factor is $\frac{1\ \text{mol}\ \ce{Fe}}{6.022 \times 10^{23}\ \text{atoms}\ \ce{Fe}}$
-
snc 1w snc 1w safety in the science lab use the graphic provided by the…
1. - Unsafe Activity 1: Jim is drinking from an unlabeled container. This is unsafe because the container could hold toxic/irritating lab chemicals, leading to poisoning or injury…
-
molarity practice problems 1) how many grams of potassium carbonate are…
1. $69.1\ \text{grams}$ 2. $0.29\ \text{liters}$ 3. $3.51\ \text{M}$ 4. $198.15\ \text{grams}$ 5. $0.85\ \text{M}$ 6. $816.5\ \text{grams}$ (rounded)
-
question 1 respond to the following based on your reading. what is the …
| Feature | Longitudinal Waves | Transverse Waves | |---------|---------------------|-------------------| | Wave-Particle Direction | Parallel | Perpendicular | | Molecular Cycle …
-
c. by studying the interactions of living organisms with their environm…
d. They are the building blocks that combine to form all substances
-
how does chemistry contribute to environmental protection? a. chemistry…
a. Chemistry helps develop cleaner energies, reduce pollution, and conserve natural resources.
-
how does chemistry contribute to environmental protection? a. by design…
c. By developing cleaner energies and reducing pollution
-
which of the following is an example of matter? a. heat b. light c. sou…
d. Water
-
what do chemists study to understand the interactions and transformatio…
c. Atoms and molecules
-
an element with mass 590 grams decays by 19.5% per minute. how much of …
$20.7$ grams
-
instructions: for each chemical equation, write the correct reaction ty…
Synthesis (Combination) Reaction ### 2.
-
examples given below underline each of these equations: a. synthesis (c…
To solve this, we need to underline each chemical equation as per the instructions. Let's go through each section: ### A. Synthesis (Combination) Reactions 1. $\underline{\ce{Na +…