Química
Reacciones químicas, estequiometría, estructuras moleculares y propiedades.
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which of the following happens during a chemical change? check all of t…
New substances with different properties are formed. Solids, liquids, or gases may form.
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analyzing chemical formulas select the description of each substance gi…
One molecule of $O_2$ is made of two oxygen atoms. The compound $Al_2O_3$ is made of two aluminum atoms and three oxygen atoms. The compound KOH is called potassium hydroxide (or …
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physical and chemical properties and changes name zach physical propert…
1. P 2. P 3. C 4. P 5. C 6. C 7. P 8. P 9. C 10. P 11. P 12. P 13. P 14. C 1. P 2. C 3. P 4. P 5. C 6. C 7. P 8. P 9. C 10. P 11. C 12. C 13. C 14. P 15. C 16. P 1. P 2. C 3. C 4.…
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① where is the location of helium, neon, and argon in the periodic tabl…
1. Group 18 2. Group 1 3. Helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), radon (Rn) 4. Non - metal; it has one valence electron and typically forms covalent bonds a…
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for questions 29 - 30, consider a compound consisting of 55.80% c, 7.04…
29. B. \(C_{2}H_{3}O\) 30. B. \(C_{6}H_{9}O_{3}\)
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among the elements of the main group, the first ionization energy incre…
A. from left to right across a period
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electronegativities of the elements na, al, p, and cl follow a specific…
Cl
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which element has a larger atomic radius than sulfur? chlorine cadmium …
B. cadmium
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which best describes ionization energy? energy needed to add an electro…
energy needed to remove an electron from an atom or ion in the gas phase
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the most negative electron affinity is most likely associated with whic…
small nonmetal atoms
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which element would most likely have an electron affinity measuring clo…
Ar
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3. there are ___ periods on the periodic table. a 7 b 8 c 17 d 18
A. 7
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which explains the change in ionization energy that occurs between remo…
The ionization energy increases because the ratio of the protons to electrons increases.
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which element has the smallest atomic radius? calcium potassium scandiu…
D. titanium
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2. which metal is liquid at room temperature and was used in early ther…
2. Mercury 3. 7
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9. the elements that behave like metals in some ways and nonmetals in o…
C. metalloids
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selected properties of antimony (sb) and iodine (i) are listed in the t…
Sb has a lower ionization energy and a lower electronegativity than I.
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which element would release the most energy while adding an electron to…
C. Br
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12. the atomic mass of an atom is the sum of: a protons and electrons b…
B. protons and neutrons
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protons and isotopes quick check beryllium has an atomic number of 4. h…
C. 5
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there are three stable forms of neon: neon-20, neon-21, and neon-22. wh…
The atomic masses differ. So the correct option is: The atomic masses differ.
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rubidium has an atomic number of 37 and a mass number of 85. how many p…
37 protons, 48 neutrons, and 36 electrons (corresponding to the second option in the multiple - choice list)
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protons and isotopes quick check an element has an atomic number of 16.…
A. A neutral atom gained 2 electrons.
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4. the elements on the left side of the periodic table are referred to …
A. metals
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protons and isotopes quick check which statement describes the number o…
The number of protons is given by the atomic number, which increases by one moving from left to right across each row of the periodic table.
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elements are organized on the periodic table based on their properties.…
Rubidium (Rb) is more reactive than sodium (Na) because the valence electrons in sodium atoms are closer to the nucleus and harder to remove.
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atoms of elements at the top of a group on the periodic table are small…
The valence electrons of the larger atoms are farther from the nucleus and are easier to remove, so the metals near the bottom are more reactive than those at the top.
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metals are used in many products because of the characteristic properti…
Tungsten is ductile, is malleable, and has a high luster.
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dicting conductivity based on the periodic table based on what you know…
Silver, Germanium, Iodine
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1. the first in time and the first in importance of the influences upon…
4. Man desires to find the interrelation of elements in nature.
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identifying properties of metalloids sort the properties of metalloids …
Metallic Characteristics: lustrous, solid at room temperature In - Between Characteristics: semiconducting Nonmetallic Characteristics: brittle, amorphous
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2. calculate the number of molecules in 2.5 mol of a substance. 0.15×10…
1.51×10²⁴ molecules
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if 1.4776 g is added to 32.32 g how many significant figures will the a…
D. four
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multiple choice question a lump of lead has a mass of 22.8 g and a volu…
11 $g/cm^{3}$
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name: fill in the blank: fill in the blank with the correct words. 1. i…
1. Matter 2. Mass 3. Weight 4. Chemical bond 5. Mixture 6. Di - atomic molecule 7. Compound 8. Intermolecular force 9. Kinetic energy 10. Endothermic 11. Solid 12. Solid 13. Solid…
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3. a balloon contains 4.50×10²¹ atoms of helium (he) gas. calculate the…
$0.299\text{ g}$
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what is the name of the bond between an anion and a cation? covalent io…
Ionic
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which subatomic particles are found within the nucleus? select all that…
Proton, Neutron
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matter can change - questions 1. matter is 2. state something you can d…
1. Anything that has mass and takes up space. 2. Heat it (or other valid answers like cool it, cut it). 3. It melts into liquid water. 4. Melts; heat it up. 5. Heat it to 100°C at…
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question where is the safety equipment located in your chemistry labora…
# Explicación paso a paso: ## Paso 1: Inspección del laboratorio Mira alrededor del laboratorio de química para identificar la ubicación de cada pieza de equipo de seguridad (exti…
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the endocrine system is a system of glands that release directly into t…
1. Hormones 2. Nervous 3. Hypothalamus 4. Pituitary 5. Thyroid 6. Metabolism 7. Parathyroid 8. Adrenal 9. Adrenaline 10. Pancreas 11. Insulin 12. Diabetes 13. Ovaries 14. Testes 1…
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grammar passage hint: most act english questions can be answered by loo…
B. its
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seleccione la respuesta correcta. ¿cuál de las siguientes es una ecuaci…
B. 2HgO → 2Hg + O2
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matt and juan are studying chemical reactions and the law of conservati…
D. Some gas escaped from the baggie before the boys had it completely closed
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a flask with vinegar in it has a mass of 160 grams. a balloon with baki…
B. 200 grams, because all the atoms remain in the balloon or flask
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sara is making an omelet. she cracks open 6 eggs and places them in a b…
A. cutting pepper B. cutting onion D. mixing eggs
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part b while studying chemical and physical changes, students added sal…
B. No, it is a physical change. It is salt and water and you can get the salt back by boiling off the water
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chemical and physical changes part a consider the images depicting chan…
D. The pipes in image I are going through a chemical change called rusting; the evidence is the color change
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chemical and physical changes part a consider the images depicting chan…
B. The papers are undergoing a physical change because they are slit papers, nothing new is formed.
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in your lab group you combined vinegar and baking soda and observed the…
A. A gas is produced C. Fizzing occurred E. There is a change in the composition of the reactants
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the law of conservation of matter tells us that the total number of ato…
A. $4NH_3 + 5O_2 ightarrow4NO + 6H_2O$ B. $8H_2S+8Cl_2 ightarrow S_8 + 16HCl$ E. $2Al(OH)_3+3H_2SO_4 ightarrow Al_2(SO_4)_3+6H_2O$
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density identifies matter part a students were given three graduated cy…
D. The liquids formed three distinct layers because of different densities
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a flask with vinegar in it has a mass of 160 grams. a balloon with baki…
B. 200 grams, because all the atoms remain in the balloon or flask
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examine the image and assess the relationship of the atoms shown by ch₄…
A. The rearrangement of atoms is a chemical change
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chemical and physical properties which image(s) shows a physical proper…
A. I B. II C. III
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matt and juan are studying chemical reactions and the law of conservati…
D. Some gas escaped from the baggie before the boys had it completely closed
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chemical and physical changes part a consider the images depicting chan…
B. The pipes are undergoing a physical change because they are still papers, nothing new is formed.
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which of the following is not a property of copper? * 1 point reddish c…
C. waxy solid that melts at 44°C
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what is the symbol for the element in period 6 and group 1? 1 point
C. Fr
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what is the symbol for the element in the second family on the third pe…
Mg
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3. identify the various types of solutions. describe the characteristic…
When using high - beams in fog, more light is scattered by the fog particles due to the Tyndall effect, reducing visibility. Low - beams have a more focused path and less scattere…
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170. vitamin e many plants contain vitamin e (c₂₉h₅₀o₂), a substance th…
The percent - composition of vitamin E is approximately $80.85\%$ carbon, $11.72\%$ hydrogen and $7.43\%$ oxygen.
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exercise 1 (a) the recommended daily allowance (rda) of the trace metal…
(a) 410000 μg/day (b) 0.9 g/day (c) 1.5 tablets (d) 0.07 mg/day
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43. classify each as a physical change or a chemical change. a. breakin…
a. Physical change b. Physical change c. Chemical change d. Chemical change e. Chemical change
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referred pain, often down the left shoulder and arm, in response to myo…
C. angina pectoris
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the sp ht$_{au}$ = 0.03050 cal/g$^{circ}$c. a sample of au lost 2.5000 …
1. $\frac{1\ g}{0.0305\ cal\times1^{\circ}C}$ 2. $2.5000\times 10^{7}\ cal$ 3. $0.0305\ cal\times25.0^{\circ}C$ 4. $3.28\times 10^{7}\ g$
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how many calories would be gained when 1.0000 x 10^6 g of gold (one of …
1. D. $0.0305\ cal/g^{\circ}C$ 2. G. $11.0^{\circ}C$ 3. H. $3.355\times 10^{5}\ cal$
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fill in the blanks with the terms provided. not all terms will be used.…
1. inflammation 2. arterioles 3. nitric oxide 4. vasoconstriction
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fill in the blanks with the terms provided. not all terms will be used.…
1. Inflammation 2. Vasodilation 3. Arterioles 4. Nitric oxide 5. Vasoconstriction
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match the definition with the appropriate hemostasis pathway. 1. begins…
1. Extrinsic pathway 2. Extrinsic pathway 3. Intrinsic pathway 4. Intrinsic pathway 5. Intrinsic pathway 6. Common pathway 7. Common pathway 8. Common pathway
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question 2 / 5 it is very dangerous to put heated glassware in cold wat…
A. true
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question 1 / 5 always look directly into the container you are heating.…
B. false
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the bohr models below show electron transitions that can occur in excit…
A. 434 nm
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the lewis diagram below represents a thallium ion. tl with two dots abo…
D. \( 3+ \)
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which of the following lewis diagrams could represent a neutral atom fr…
C
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the lewis diagram below represents an aluminum ion. alⁿ what is the val…
D. \(3+\)
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fill in the blank question dyes are frequently used as ph indicators in…
titration (or chemical, but titration is more specific for pH indicator use in a common lab context)
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which of the following is the correct bohr model for a neutral carbon a…
B
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h h:n:h based on the lewis diagram for nh₃ shown above, the h-n-h bond …
C. \( 109.5^{\circ} \)
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which of the following correctly compares the strength of the two carbo…
A. The carbon - to - carbon bond on the left is stronger because it is a double bond.
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which of the following lewis diagrams represents a molecule that is pol…
C. $\ce{:\overset{..}{Cl}:\overset{..}{Cl}C:H}$ (or the Lewis diagram for $\ce{CH2Cl2}$ as shown in option C)
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12 mark for review $ddot{\text{o}}=\text{c}=ddot{\text{o}}$ \t $ddot{\t…
A. Diagram 1, because all the atoms have a formal charge of 0.
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based on formal charges, which of the following is the best lewis elect…
A. \(\ce{\overset{H}{\underset{H}{:N}-\overset{..}{O}-H}}\) (with the overall charge of \(+1\) as shown in the diagram)
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this image shows someone practicing good hygiene. what does this hygien…
the transmission of disease
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10 mark for review diagram 1: h-c-h (single bond to o with :o: lone pai…
D. Diagram 2, because all atoms have a formal charge of 0.
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9 mark for review the diagram above best illustrates which of the follo…
B. Malleability, because it shows how adjacent layers of positive ions can move relative to one another while remaining in full contact with the electron sea.
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electronic configurations: directions: for each element or ion give the…
### For $\boldsymbol{\ce{Na+}}$ (First, correct the initial mistakes in the given work): #### Full Electron Configuration: Sodium atom ($\ce{Na}$) has 11 electrons, $\ce{Na+}$ los…
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which of the following indicates whether the solid substance represente…
B. It conducts electricity because electrons are free to move through the substance.
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the particles in solid ki, a stable ionic compound, are arranged to max…
A
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the particulate - level diagram shown above best helps to explain which…
B. Brittleness
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molten (liquid) nacl is represented by the particulate diagram shown ab…
B. It conducts electricity because ions are free to move
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3 mark for review which of the following claims about a binary compound…
B. The bonding in the compound is nonpolar covalent.
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2 mark for review which of the following claims about a binary compound…
D. The electronegativity difference between the elements in the compound is relatively large.
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on the basis of electronegativity differences between atoms, which of t…
D. There is ionic bonding between $\ce{Mg^{2+}}$ ions and $\ce{NO^{-}_{3}}$ ions
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if you used a much larger sample of fresnocitium, would it make a subst…
Using a much larger sample of fresnocitium would not make a substantial difference to the calculated average atomic mass. This is because the average atomic mass depends on the re…
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complete the table below by filling in the principal quantum number n a…
- \( 4s \): \( n = 4 \), \( l = 0 \) - \( 5d \): \( n = 5 \), \( l = 2 \) - \( 2p \): \( n = 2 \), \( l = 1 \) - \( 6f \): \( n = 6 \), \( l = 3 \)
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here is a sketch of a 1s orbital: image of 1s orbital with x, y, z axes…
| point A | point B | compare \( P_A \) to \( P_B \) | |---------|---------|-------------------------------| | 10 pm to the left of the nucleus, along the -x axis. | 10 pm above t…
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13-14. solid substance a has a melting point of 100°c. liquid substance…
### Substance A at 115°C - **State**: Liquid - **Description**: The temperature \( 115^\circ\text{C} \) is above substance A’s melting point (\( 100^\circ\text{C} \)), so it is li…
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13-14. solid substance a has a melting point of 100°c . liquid substanc…
### Substance A at 115°C - **State**: Liquid - **Description**: The melting point of solid substance A is \( 100^\circ \text{C} \). At \( 115^\circ \text{C} \) (which is above the…
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question 3 what nuclide has has 9 protons and 10 neutrons. ○ fluorine-1…
A. fluorine - 19 ### Question 4