Química
Reacciones químicas, estequiometría, estructuras moleculares y propiedades.
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question 3 what determines a minerals unique characteristics? chemical …
Chemical composition and crystal structure
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3. after completing an experiment, all chemical wastes should be * left…
3. B. disposed of according to your instructor's directions 4. A. discuss the issue with your instructor
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how can the ratio of different elements affect matter? a it affects the…
C. It affects the physical and chemical properties of matter.
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what is formed when two or more atoms link up? a element b molecule c p…
B. molecule
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a molecule of water contains one atom of hydrogen and two atoms of oxyg…
FALSE
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a nucleus contains protons and electrons. true false
FALSE
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choose the correct answer. which atmospheric gas is being described? a …
D. argon
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an atom that loses or gains electrons to become either negatively or po…
ion
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the nucleus of an atom contains protons and what other particle? enter …
neutrons
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which of the following make up the nucleus of an atom? select all that …
A. neutron C. proton
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unit 3 comprehensive quiz l how many moles are in 54.3 grams of na? o 5…
2.36 moles
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what conversion factor should be used to convert 2.48 moles of ca to gr…
$2.48\text{ moles Ca}\times\frac{40.078\text{ grams Ca}}{1\text{ mole Ca}}$ (The third - option you provided has an incorrect value in the numerator, and the correct one is not am…
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match the following particle diagrams to their correct terms. element c…
First diagram: mixture Second diagram: compound Third diagram: element
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which of the following best describes isotopes of an element? atoms wit…
Atoms with the same number of protons but different numbers of neutrons
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how many moles are in 5.2 x 10^{23} atoms of barium? 0.864 mol 3.1 x 10…
0.864 mol
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why is radioactive dating important when approximating the age of earth…
Scientists can determine the order of when rocks formed on Earth.
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which of the following quantities is best represented by a mole? the nu…
The number of particles of water in a lake
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unit 3 comprehensive quiz e possible points 5 which element has a molar…
D. Al
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the english chemist john dalton formulated an atomic theory based on hi…
1. All elements are made up of tiny indivisible particles called atoms.
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unit 3 comprehensive quiz l possible points: 5 which statement correctl…
Protons and neutrons have nearly the same mass, while electrons are much lighter.
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unit 3 comprehensive quiz e possible points 5 a sample composed only of…
C. an element
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identify whether longhand notation or noble - gas notation was used in …
Potassium (K): longhand notation Iron (Fe): noble - gas notation Argon (Ar): noble - gas notation
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unit 3 comprehensive quiz l where in the atom are protons located? nucl…
A. nucleus
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4. which of the following describes the difference between weathering a…
4. weathering is the breaking down of rocks while erosion is the movement of the rocks by wind, ice, or water from one place to another 5. the sand component of soil
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match each atomic model to its description. possible points: 5 daltons …
- Dalton's Model (first atomic model): Atoms of any one element are identical to each other but different from atoms of other elements. Atoms combine in different whole number rat…
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which energy level (orbit) has electrons with least amount of energy? p…
The innermost orbit
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review questions: 1. why is the water molecule so important to organism…
1. Water is a universal solvent, participates in biochemical reactions, helps in temperature - regulation, and provides turgor pressure in plants. 2. Hydrogen ions ($H^+$) and hyd…
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the complete lewis electron - dot diagram for hconh₂ is shown above. id…
B. $sp^{2}$ hybridized and $120^{\circ}$
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read shakespeares \sonnet 100.\ where art thou, muse, that thou forgets…
C. cdcd
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when olive oil and sodium hydroxide are mixed together, soap and glycer…
C. This is a chemical reaction because new substances (soap and glycerol) are made.
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question: 6 of 10 melting point: -7℃ boiling point: 79℃ nonmagnetic sol…
D. All four samples are from different substances.
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a student measures some physical properties of different substances. th…
B. G and I: boiling and melting point H and J: density
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students are asked to classify these substances based on their physical…
| Help | Not Help | |--|--| | Conductivity in water, Density, Solubility | Color, Magnetism, Mass |
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8. how many electrons, protons, and neutrons are found in each of the f…
a) Electrons: 12, Protons: 12, Neutrons: 12 b) Electrons: 10, Protons: 11, Neutrons: 12 c) Electrons: 17, Protons: 17, Neutrons: 18 d) Electrons: 18, Protons: 17, Neutrons: 18 e) …
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1. estimate the mass of one ¹⁴c atom (in amu) as precisely as you can (…
14 amu
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what makes an atom? provide an answer in complete sentences that descri…
An atom is composed of a nucleus with protons and neutrons, and electrons that orbit the nucleus. The number of protons in the nucleus is the atomic number, which defines the elem…
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12. describe what the isotopes of an element have in common and how the…
Isotopes of an element have the same number of protons. They differ in the number of neutrons.
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17. even a slight change in ph can be harmful! how do buffers moderate …
Buffers contain a weak - acid/conjugate - base or weak - base/conjugate - acid pair. They react with added acids or bases to resist pH changes.
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12. describe what the isotopes of an element have in common and how the…
1. The mass of one $^{14}$C atom is approximately 14 amu because it has 2 more neutrons than $^{12}$C and the mass of a neutron is approximately 1 amu. 2. a) The mass of an electr…
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considering the role of enthalpy in choosing energy sources many fuels,…
The enthalpy of combustion is a large negative value. Burning hydrocarbons produces a lot of energy.
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chemactivity 1 what makes an atom? 11. complete the following table. is…
| Isotope | Atomic Number (Z) | Mass Number (A) | Number of Electrons | |---|---|---|---| | \(^{59}Co^{2+}\) | 27 | 59 | 25 | | \(^{14}N\) | 7 | 14 | 7 | | \(^{7}Li\) | 3 | 7 | 3 …
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the actual enthalpy of the magnesium flare reaction is -603 kj/mol. you…
The coffee cup calorimeter may have absorbed some heat. The thermometer did not measure the temperature of the solution properly. Reading the maximum temperature values from the t…
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2. interactions between spheres involve movement of energy and/or matte…
Possible spheres: biosphere, atmosphere, hydrosphere. Interactions: Chemicals from spraying moving from atmosphere to biosphere; water evaporation from hydrosphere to atmosphere a…
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13. consider coffee to which you have added sugar. which of these is th…
13. Solute: Sugar; Solvent: Coffee 14. It is a polar molecule, enabling interaction with ionic and polar covalent compounds. 15. Hydrophobic: Repel water, e.g., oil; Hydrophilic: …
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11. complete the following table. isotope atomic number z mass number a…
**: Isotopes of an element have the same number of protons (and thus the same atomic number), which gives them the same chemical properties. They differ in the number of neutrons,…
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determining and interpreting the enthalpy of the magnesium combustion r…
There seems to be an error in the provided answer - options as the calculated value is - 569 kJ/mol and it is not among the given options (-817, -654, -245). If we assume there is…
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analyzing the intermediate reactions if you reverse reaction 2 and comb…
H₂O, H₂
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directions: answer each question by circling the correct choice. after …
1. C. produces ($H^+$) ions in water 2. B. turns blue litmus paper red 3. C. bases 4. B. bases 5. C. acidic 6. A. acids 7. A. pH 3 8. A. acids 9. B. base 10. B. Red litmus paper s…
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reflecting on the laboratory experiment. to find the enthalpy of a reac…
First blank: mass Second blank: temperature
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reflecting on the laboratory experiment. a law allows you to find the n…
Hess
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reflecting on the laboratory experiment. what were the learning goals o…
1. to compute the enthalpy of a reaction that cannot be measured directly using a simple calorimeter 2. to compute a reaction's enthalpy directly using mass measurements and a cal…
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what is the purpose of safety data sheets? o to list information such a…
To list information such as precautions and possible hazards of a chemical
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understanding concepts 1. what is \combustion\? 2. (a) when fossil fuel…
1. Combustion is a rapid oxidation process with heat and light production. 2. (a) Fossil - fuel and oxygen. (b) Carbon dioxide and water. (c) Due to impurities in fossil - fuels. …
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how do you see the concept of hybridization being applied in real - wor…
Hybridization affects molecular shape, bond angles, reactivity. Examples: $CH_4$ with $sp^3$ hybridization (tetrahedral, affects substitution reactions); $C_2H_4$ with $sp^2$ hybr…
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3 which of the following is not a subatomic particle found in an atom? …
B. Nucleus
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2 all matter is made up of... a. cells b. atoms c. organelles d. mixtur…
B. Atoms
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2 all matter is made up of... a. cells b. atoms c. organelles d. mixtur…
B. Atoms
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3 which of the following is not a subatomic particle found in an atom? …
B. Nucleus
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phet exercises 16. the periodic table has a great deal of information a…
a) 17 b) 74 c) 17 d) 52 e) No
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which are classifications of fatty acids? o saturated and unsaturated o…
Saturated and unsaturated
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understanding concepts 1. what is \corrosion\? 2. how is an oxide forme…
1. Corrosion is the deterioration of metals due to environmental reactions, often oxidation. 2. An oxide is formed when a substance reacts with oxygen through an oxidation - reduc…
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12. play with the simulation to determine (make sure all boxes are clic…
12. a) Protons and neutrons b) Electrons 13. b) 17 c) 18 d) Number of protons e) Number of neutrons 14. Same atomic number, different mass numbers 15. Isotopes
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groups of atoms that are added to carbon backbones and that give organi…
functional
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part iii: isotopes 12. play with the simulation to determine (make sure…
Protons and neutrons ## Step2: Determine particles not affecting atom stability Electrons are in the electron - cloud outside the nucleus and do not directly affect nuclear stabil…
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the term that refers to the sum of all the chemical reactions in the bo…
Metabolism
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which of the following will, in general, increase the rate of a reactio…
Increasing concentration of reactants, Increasing temperature
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2. a fly spray accidentally sprayed onto open food on a preparation tab…
# Breve explicación: La pulverización accidental de un insecticida (un producto químico) sobre alimentos en una mesa de preparación es un ejemplo de contaminación química. Las otr…
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eral, a process that involves the formation or breakdown of molecules i…
reaction
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glucose is a ______ of starch. o polymer o monomer o functional group o…
B. monomer
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which of the following is a definition of energy? o the tendency of one…
The capacity to do work
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carboxyl and phosphate groups are examples of ________. free radicals o…
D. functional groups
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substances that are physically blended but not chemically bound are cal…
mixtures
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art-111-z191 2025fa - art appreciation / module 4 september 8 - 14 / ch…
False
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which of the following would give you the molarity of a solution? o mol…
Moles/liter
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to a certain point, increasing the concentration of reactants in a solu…
B. increase
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a proton (h⁺) donor, or a chemical that releases protons into solution,…
acid
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a chemical reaction is a process in which a covalent or ionic bond is b…
True
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in a solution, the solvent is ______ the solute. o more abundant than o…
more abundant than
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which is a hydrophobic substance? o fats o water
Fats
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a molecule may be composed of one element or more than one element. tru…
True
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hcl is a compound that releases hydrogen ions when put into water. ther…
acid
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an atom or molecule that has gained or lost electrons is called a(n)
ion
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in a solution, the more abundant substance that dissolves another subst…
A. Solvent
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deuterium and tritium are isotopes of hydrogen. what is different about…
They have different numbers of neutrons.
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hydrophobic means that a substance is insoluble in
water
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substances that are physically blended but not chemically bound are cal…
Mixtures
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atoms that make up molecules _______. o must be identical o may be iden…
B. may be identical or different
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what is an ion? o an atom that has gained or lost electrons o an atom w…
An atom that has gained or lost electrons
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isotopes differ from one another by containing different numbers of whi…
B. Neutrons
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which is an uncharged particle found in the nucleus of an atom? neutron…
Neutron
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multiple choice question which term defines the simplest form of matter…
Element
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c) ______________ is a mixture in which the composition is not uniform …
c) Heterogeneous mixture d) Homogeneous mixture
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a) element is a pure substance containing only one type of atoms. b) is…
a) An element b) A compound
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q2. fill in the blanks with suitable words. a) __________________ is a …
Element
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7. what does it mean to be a carbon sink?
A carbon sink is a natural or artificial reservoir that accumulates and stores some carbon - containing chemical compounds for an indefinite period. It removes carbon dioxide (CO₂…
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which of the following is an endothermic source of energy? ○ melting ic…
Melting ice cube
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18. what is a polymer? what is a monomer? 19. using figure 3.7a in your…
A polymer is a large molecule composed of repeating monomer subunits. A monomer is a small molecule that can join with other monomers to form a polymer. The reaction where monomer…
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21. let’s look at carbohydrates, which include sugars and starches. fir…
21. Monosaccharides 22. a. $\mathrm{C}_{6}\mathrm{H}_{12}\mathrm{O}_{6}+\mathrm{C}_{6}\mathrm{H}_{12}\mathrm{O}_{6} ightarrow\mathrm{C}_{12}\mathrm{H}_{22}\mathrm{O}_{11}+\mathrm{…
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how many moles of iron is needed if 4800 kj of energy is released from …
12.86 mole
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part 4: sedimentary rock practice. use the earth science reference tabl…
- The grain - size range of siltstone is 0.004 to 0.0625 cm. - Shale is made up of particles smaller than 0.004 cm. - Rock salt is composed of halite. - Limestone is composed of c…