化學
化學反應、化學計量、分子結構與元素性質。
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which ion in the ground state has the same electron configuration as an…
3. $F^-$
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as the atomic number increases in group 2 from be to ba, the first ioni…
2. decreases, and the atomic radius increases
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at stp, which property of tungsten remains the same for all samples of …
1. density
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diamond and graphite are two forms of solid carbon. these two forms of …
1. different crystal structures and different properties
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q2 chemistry: u4l11 covalent lewis dot diagram day 2 5. **nitrogen trii…
Covalent #### b. Formula:
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scientists sometimes want to show whether more energy is used or releas…
glucose + oxygen → carbon dioxide + water + energy
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in a chemical process, the atoms in the reactants are arranged differen…
First blank: broken Second blank: formed
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prepwork: covalent compounds name: for each molecule below, draw the le…
### 1. $\boldsymbol{CF_4}$ #### Lewis Dot Diagram: - Carbon (C) is central, has 4 valence electrons. - Four Fluorine (F) atoms, each with 7 valence electrons. - C forms 4 single b…
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37. \\( \\ce{h2s(g) + h2o2(aq) -> s8(s) + h2o(l)} \\) \\( \\ce{h2s(g) +…
The balanced chemical equation is \( \boldsymbol{\ce{8H2S(g) + 8H2O2(aq) -> S8(s) + 16H2O(l)}} \) (or can be simplified by dividing all coefficients by 8: \( \ce{H2S(g) + H2O2(aq)…
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look at the models and the table below. they show different chemical bo…
- the combination of atoms - the combination of bonds - the arrangement of atoms
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in a chemical process such as cellular respiration, the reactants and t…
| Chemical bonds | Glucose | Oxygen | Carbon dioxide | Water | |------------------------------------|---------|--------|----------------|-------| | a carbon atom connected to anot…
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for each of the following covalent compounds, provide the missing formu…
Name: dibromine monoxide Lewis Dot diagram: Br (:::Br) - O (::) - Br (:::Br) (where : represent lone pairs, and - is a single bond; each Br has 3 lone pairs (6 electrons) and O ha…
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for each of the following compounds, provide the missing formula or nam…
Name: dibromine monoxide Lewis Dot diagram: (O in center, single bonds to two Br atoms. Each Br has 3 lone pairs (6 electrons), O has 2 lone pairs (4 electrons)) ### Question 2
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2. balance the following redox reaction which takes place in a basic so…
# Explanation: ## Step1: Identify Oxidation and Reduction Half - Reactions - **Oxidation (Al to \(Al(OH)_4^-\))**: - The oxidation state of Al in \(Al(s)\) is 0, and in \(Al(OH)_4…
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5) kmno₄ 1×39.1 + 1×54.9 + 4×16.0 = 39.1 + 54.9 + 64.0 = 158.0 g/mol % …
H: \( \boldsymbol{2.74\%} \) Cl: \( \boldsymbol{97.26\%} \) ### Problem 7: NaNO₃
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6. examine the number of electrons in the energy levels for each atom. …
- **Helium (He, \(Z = 2\))**: Energy level 1 (\(n = 1\)) has 2 electrons (matches \(2n^2\) for \(n = 1\)). Total electrons = 2 (equal to protons, \(Z = 2\)). - **Oxygen (O, \(Z = …
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q2 chemistry: u4l10 covalent lewis dot diagrams day 1 date: 9. which gr…
Group 1 (Hydrogen) and Group 17 (Halogens, e.g., F, Cl, Br, I) cannot form more than one bond (single bond) in covalent compounds. Because H needs 1 electron to complete its duet,…
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the correct name for kn is potassium nitrate true false
FALSE
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correctly name the compound $ba_3p_2$. a barium phosphide b tribarium d…
a. barium phosphide
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correctly name the compound $\\ce{rb_{2}o}$. a dirubidium oxygen b diru…
c. rubidium oxide
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which is the correct order for the names and formulas of binary ionic c…
d. metal cation followed by nonmetal anion
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which is the formula for a binary ionic compound composed of iodine and…
b. NaI
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what is the name of the compound formed from na⁺¹ and p⁻³? a sodium pho…
a. sodium phosphide
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what is the overall electrical charge for any compound? a positive only…
c. neutral or no charge only
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when writing the name or formula for an ionic compound, the order they …
a. metal cation first then non - metal anion
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what is the name of the binary ionic compound of calcium and sulfur? a …
a. calcium sulfide
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choose the name of a $mgcl_2$ compound. a caesium oxide b manganese iod…
d. Magnesium chloride
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review: ionic compounds & lewis diagrams for each of the element pairs,…
### Part 1: Ionic Compounds & Lewis Diagrams (Element Pairs) #### 1. Beryllium & Bromine **Step 1: Determine oxidation states** Beryllium (Be) is in Group 2, so it has a +2 oxidat…
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name: teacher: schools q2 chemistry: u4l12 polyatomic ions date: prepwo…
### Part 1: Writing Chemical Formulas #### a. Lithium Phosphate # Explanation: ## Step1: Identify ions. Lithium ion: $Li^+$; Phosphate ion: $PO_4^{3-}$. ## Step2: Balance charges.…
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add the following measurements and type the sum into the text box. make…
169.0
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question 4 1 pts which of the following formations is a physical proper…
Can be stretched into wire.
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question 3 which is a chemical property of copper? ○ is a solid at room…
reacts in air to form a green layer
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question 2 which of the following is a physical property? ○ explosive ○…
melting point
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question 1 1 pts which is not a chemical change? ingredients for a cake…
ingredients for a cake are stirred together
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physical science review: matter and change classifying matter all matte…
| Matter | Mixture | Hetero | Homo | Substance | Element | Compound | |-------------------------|---------|--------|------|-----------|---------|----------| | 1. chlorine | | | | …
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physical science review: matter and change separating mixtures taking a…
1. You can separate sand and water by pouring the mixture through filter paper in a funnel; the water will pass through the filter paper, and the sand will be trapped on the paper…
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homogeneous vs. heterogeneous mixtures a homogenous mixture is a mixtur…
21. O (uniform composition, no visible separation) 22. E (distinct cherry/vanilla chunks) 23. E (separates into oil/water layers) 24. O (pure substance, uniform composition) 25. E…
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substances vs. mixtures a substance is matter for which a chemical form…
1. S sodium 2. S water 3. M soil 4. M coffee 5. S oxygen 6. S alcohol 7. S carbon dioxide 8. M cake batter 9. M pure air 10. M soup 11. S iron 12. M salt water 13. M ice cream 14.…
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physical science review: matter and change physical vs. chemical proper…
### Properties (C = Chemical, P = Physical) 1. P blue color 2. P density 3. C flammability (burns) 4. P solubility (dissolves) 5. C reacts with acid 6. C supports combustion 7. P …
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part b: short answer and calculations (thinking and inquiry and applica…
- Oxidation half - reaction: \(Mg_{(s)} ightarrow Mg^{2+}_{(aq)} + 2e^-\) (oxidation, 2 electrons lost) - Reduction half - reaction: \(2Ag^{+}_{(aq)}+2e^- ightarrow 2Ag_{(s)}\) (r…
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q. 6. nitrogen gas reacts w h ydrogen gas to form ammonia gas. ans. q. …
$\ce{N2 + 3H2 -> 2NH3}$ ### Q.7
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q. 2. when methane gas burns in oxygen gas, carbon dioxide gas and wate…
To solve these problems, we need to write the balanced chemical equations for each reaction. Let's tackle each question one by one: ### Q.2: When Methane gas burns in Oxygen gas, …
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read shakespeare’s \sonnet 19.\ devouring time, blunt thou the lion’s p…
- the abab, cdcd, efef, gg rhyme scheme - the widespread use of iambic pentameter - the fact that the final lines summarize the preceding lines
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calculate the molar mass of co₂. 14 g/mol 28 g/mol 44 g/mol 36 g/mol
The option with "44 g/mol" (the orange - colored option, assuming the orange option is labeled with 44 g/mol among the given choices). If we consider the options as presented (wit…
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what id the molar mass of uf₆? 101 g/mol 352 g/mol 257 g/mol 238 g/mol
352 g/mol (corresponding to the purple option: 352 g/mol)
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what is the molar mass of cl₂? 71.0 g/mol 17 g/mol 89 g/mol 35.5 g/mol
A. 71.0 g/mol
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calculate the molar mass of koh. 84 g/mol 56 g/mol 28 g/mol 112 g/mol
B. 56 g/mol (assuming the purple option is labeled B, with text "56 g/mol")
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calculate the molar mass of ba(c₂h₃o₂)₂ 255.3 g/mol 196.3 g/mol 237.3 g…
255.3 g/mol (corresponding to the yellow option: 255.3 g/mol)
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practice: what is a mole? which of the following is not true? the mole …
The option that is NOT true is: There are $2.06\times10^{20}$ atoms in a mole
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practice: what is a mole? in a 1.5 mole sample of water, h₂o, how many …
First box: \( 9.03 \times 10^{23} \), Second box: molecules
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practice: what is a mole? how many particles are found in 3.00 moles of…
First box: \( 1.81\times10^{24} \) Second box: atoms
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identify the formula units for each particle. not all units will be use…
- \( \ce{CO_2} \): moles, molecules - \( \ce{Fe_2O_3} \): moles, formula units - \( \ce{Li} \): moles, atoms - \( \ce{Br_2} \): moles, molecules (If we are to match each compound …
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2c₂h₆ + 7o₂ = 4co₂ + 6h₂o determine how many grams of ethane (c₂h₆) are…
\(39.1\) (or more precise \(39.11\))
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2kclo₃ = 2kcl + 3o₂ determine how many moles of oxygen gas are produced…
The number of moles of oxygen gas produced is approximately $\boxed{5.11}$ moles (or more precisely, using exact calculation, it's approximately 5.11 moles). Wait, but let's check…
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how many particles are found in 3.00 moles of aluminum, al? in the firs…
The amount is \( 1.81\times 10^{24} \) and the unit is atoms. So the first box should have \( 1.81\times 10^{24} \) and the second box should have atoms.
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identify the formula units for each particle. not all units will be use…
- \( \text{N}_2 \): molecules (and moles) - \( \text{SrCl}_2 \): formula units (and moles) - \( \text{Ca} \): atoms (and moles) - \( \text{NO} \): molecules (and moles) But based …
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identify the formula units for each particle. not all units will be use…
- \( \text{CO}_2 \): molecules (or moles, but based on particle type, molecules) - \( \text{Fe}_2\text{O}_3 \): formula units - \( \text{Li} \): atoms - \( \text{Br}_2 \): molecul…
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which of the following is not true? the mole is equal to avogadro’s num…
There are $2.06\times 10^{28}$ atoms in a mole
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which of the following correctly shows the relationship, in terms of nu…
1 mole of water = 1 mole of helium = 1 mole of aluminum
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how many particles are there in 2.46 moles of potassium chlorate, kcl? …
The correct amount is \( 1.47\times 10^{24} \) and the correct unit is formula units. So in the first box: \( 1.47\times 10^{24} \), in the second box: formula units.
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in a 1.5 mole sample of water, h₂o, how many particles are present? in …
First box: \(9.03\times10^{23}\) Second box: molecules
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what is the molar mass of ca(oh)₂? 58.10 g/mol 74.10 g/mol 114.18 g/mol…
74.10 g/mol (corresponding to the purple option: 74.10 g/mol)
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what is the molar mass of mgf₂? 43.31 g/mol 86.62 g/mol 67.62 g/mol 62.…
62.31 g/mol (the option with 62.31 g/mol, likely the fourth option: 62.31 g/mol)
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7. ice wedging is the freezing and expansion of water that has entered …
a. TRUE ### Question 8
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multiple choice questions answer the following multiple choice question…
1. A. An increase in heat energy 2. D. How much thermal energy it can transfer 3. B. Heat is the total energy of moving molecules, and temperature is the average energy.
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answer the following multiple choice questions about the reading. 1. ac…
1. A. How much the particles in a substance are moving. 2. A. They move more slowly. 3. C. The temperature at which particles have the least amount of motion.
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lewis structures refresher name: date: objective: review valence electr…
s (Summary) #### Part 1 a. \( \text{H} \), 1 valence electron, \( \text{H} \cdot \) b. \( \text{C} \), 4 valence electrons, \( \cdot \text{C} \cdot \) (with dots on all four sides…
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3. a chemistry experiment calls for no more than 0.225 ounce of acid. w…
D. 0.22
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vraag 2 willem heeft tijdens zijn vakantie een stuk metaal gevonden. hi…
The metal is most likely nickel (density $\approx 8.66\ \text{g/mL}$, closely matching nickel's typical density of $8.9\ \text{g/mL}$).
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two iron rods are placed horizontally, touching end - to - end. one end…
D. The molecular movement in the first rod transferred energy to the molecules in the second
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hazcom training teaches us about hazardous chemicals. which of the prod…
A. Aerosols
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the graph shows how many grams of the solids sodium chloride, potassium…
D. As the temperature of the water increased, more grams of each solid dissolved.
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≡c - ch₂ - ch₃ (with a ch₃ branch on the ch₂) + k₂cr₂o₇ + hno₃ →
To balance the redox reaction involving the organic compound (let's assume the organic compound is a hydrocarbon derivative, here we can analyze the oxidation states first), $\ce{…
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the symbol of an unprefixed scientific unit has been left off of each m…
- the mass of a can of soda: 355 g - the volume of tea in a typical teacup: 0.2 L (or 0.2 dm³, but more likely L) - the world record for the 100m dash: 9.6 s - the width of a two …
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the symbol of an unprefixed scientific unit has been left off of each m…
- the length of a car = 5. $\boldsymbol{m}$ (meters) - the length of a pencil = 0.15 $\boldsymbol{m}$ (meters) or 0.15 $\boldsymbol{dm}$ (decimeters) but more likely meters (since…
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the symbol of an unprefixed scientific unit has been left off of each m…
To solve for the missing units, we analyze each measurement: ### 1. Typical time between eye blinks Eye blink duration is short, measured in milliseconds? No, typical blink time i…
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the symbol of an unprefixed scientific unit has been left off of each m…
- the mass of an apple = 250 g - how long a typical TV ad lasts = 30 s - the width of a two - lane road = 10 m - the volume of gas in a car’s full gas tank = 50 L
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fill in the missing information: | element name | element symbol | | --…
| element name | element symbol | | ---- | ---- | | Fluorine | F | | Potassium | K | | Chlorine | Cl | | Silicon | Si | | Aluminum | Al | | Xenon | Xe |
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fill in the missing information: | element name | element symbol | | --…
| element name | element symbol | | ---- | ---- | | carbon | \( C \) | | sodium | \( Na \) | | nitrogen | \( N \) | | zinc | \( Zn \) | | bromine | \( Br \) | | gold | \( Au \) |
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complete the table below. | $square$ kl $=$ 5000 l | 2000 mg $=$ $squar…
- \( 5 \) kL \( = 5000 \) L - \( 2000 \) mg \( = 2 \) g - \( 6 \) Mm \( = 6000000 \) m - \( 60 \) ds \( = 6 \) s (If we fill the table cells in order: first cell: 5; second cell: …
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complete the table below. □ dm = 6 m □ mg = 3 000 000 g 300 cs = □ s 6 …
- For \( \square\space dm = 6\space m \): \( 60 \) - For \( \square\space Mg = 3000000\space g \): \( 3 \) - For \( 300\space cs = \square\space s \): \( 3 \) - For \( 6\space kL …
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complete the table below. for example, in the first row decide whether …
| Element | Symbol of most likely ion | Type of ion | |-----------|---------------------------|-------------| | Scandium | $\text{Sc}^{3+}$ | cation | | Chlorine | $\text{Cl}^{-}$…
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classify each chemical compound: | compound | type of compound | | ----…
For \( \text{Cl}_2\text{O}_7 \), the type of compound is molecular. So we should select the "molecular" option for \( \text{Cl}_2\text{O}_7 \).
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classify each chemical compound: | compound | type of compound | | ----…
- \( \text{HClO}_4 \): ionic - \( \text{Fe(CN)}_3 \): ionic - \( \text{FeS} \): ionic
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fill in the missing information: | symbol | atom or ion? (check all tha…
- \( \text{B}^{2+} \): cation, protons = 5, electrons = 3 - Sn: neutral atom, protons = 50, electrons = 50 - Missing symbol: \( \text{Br}^- \), anion, protons = 35, electrons = 36
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how many protons and neutrons are in an atom of $^{209}$bi? number of p…
Number of protons = 83, Number of neutrons = 126
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how many protons and neutrons are in an atom of yb-168? number of proto…
Number of protons = 70 Number of neutrons = 98
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a chemist determined by measurements that 0.0550 moles of silver partic…
\( 6.03 \, \text{g} \)
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a chemist weighed out 4.3 g of mercury. calculate the number of moles o…
0.021 (or $2.1\times10^{-2}$) mol
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complete the table below. some binary molecular compounds name | chemic…
| Name | Chemical Formula | |---------------------|------------------| | sulfur monochloride | \( SCl \) | | pentasulfur dinitride | \( S_5N_2 \) | | sulfur tetrachloride | \( SCl…
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what is the total number of oxygen atoms on the right - hand side of th…
6
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what is the total number of oxygen atoms on the left - hand side of thi…
7
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how many protons are in a neutral atom of beryllium (be)? how many elec…
Number of protons = 4; Number of electrons = 4
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how many protons are in a neutral atom of calcium? how many electrons? …
Number of protons = 20 Number of electrons = 20
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in what period is selenium? in what group? period = group =
Period = 4 Group = 16
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in what period is argon? in what group? period = group =
Period = 3 Group = 18
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write the chemical symbol for an element in period 6 and group 3a.
$\text{Tl}$
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write the chemical symbol for an element in period 6 and group 8a.
$\text{Rn}$
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a balloon is filled with 8.964 liters of he at stp. how many moles of h…
0.4 moles
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fill in the missing information: | element name | element symbol | | --…
| element name | element symbol | |--------------|----------------| | chlorine | $Cl$ | | nitrogen | $N$ | | carbon | $C$ | | silicon | $Si$ | | phosphorus | $P$ | | manganese | $…