Answer:
True
Explanation:
The unit cell is the smallest group of atoms which has the overall symmetry of a crystal, and from which the entire lattice can be built up by repetition in three dimensions (Oxford dictionary).
The number of atoms in a unit cell of a crystal structure must be equal to or a multiple of the number of atoms in the empirical formula of the compound. In other words, the unit cell should contain the formula unit of the compound.
what was the area of the himalayas like 40 million years ago
Answer:
yeskkfslszv
Explanation:
frgkkfsssssssss
Answer:
They were relatively flat.
Write the chemical formula for this molecule O=N-CI
Explanation:
Structural Formulas v. Empirical Formulas
An empirical formula (like a molecular formula) lacks any structural information about the positioning or bonding of atoms in a molecule. It can therefore describe a number of different structures, or isomers, with varying physical properties. For butane and isobutane, the empirical formula for both molecules is C2H5, and they share the same molecular formula, C4H10. However, one structural representation for butane is CH3CH2CH2CH3, while isobutane can be described using the structural formula (CH3)3CH.
The following aqueous solutions of are mixed: 100.0 mL of 1.00 M lithium bromide and 100.0 mL of 1.00 M lead (II) nitrate. In an organized and clear manner, show all of your work and answers for this problem on the uploaded work. (a) Write the molecular equation for this reaction. (b) Write the total ionic chemical equation for this reaction. (c) Write the net ionic chemical equation for this reaction. (d) Identify the spectator ions in this reaction. (e) Identify the limiting reactant. (f) Determine the mass of solid product that is formed?
Answer and Explanation:
(a) When lithium bromide (LiBr) solution is mixed with a solution of lead (II) nitrate (Pb(NO₃)₂), lithium nitrate (LiNO₃) and lead (II) bromide (PbBr₂) are formed, according to the following molecular equation:
2LiBr(aq) + Pb(NO₃)₂(aq) → 2LiNO₃(aq) + PbBr₂(s) ↓
As the product PbBr₂ is an insoluble solid, it precipitates (↓).
(b) The total ionic equation is written with all ions of the reaction - no matter if they participate in the precipitate formation or not:
2Li⁺(aq) + 2Br⁻(aq) + Pb²⁺(aq) + 2NO₃⁻(aq) → 2Li⁺(aq) + 2NO₃⁻(aq) + PbBr₂(s)
(c) The net ionic equation is written including only the ions which participate in the precipitate formation. In this case, the precipitate is PbBr₂, and it is formed by Pb²⁺ and Br⁻ ions:
Pb²⁺(aq) + 2Br⁻(aq) → PbBr₂(s)
(d) The spectator ions are those which do not participate in the formation of the precipitate. From the total ionic equation, we can see that Li⁺ and NO₃⁻ ions are repeated on both sides of the equation, so they are redundant. Thus, the spectator ions are Li⁺ and NO₃⁻ ions.
(e) To identify the limiting reactant, we first calculate the moles of each compound as the product of the solution concentration and volume:
For LiBr:
C = 1.00 M = 1 mol/L
V = 100.0 mL x 1 L/1000 mL = 0.1 L
moles of LiBr = 0.1 L x 1.00 mol/L = 0.1 mol
The same for Pb(NO₃)₂:
C = 1.00 M = 1 mol/L
V = 100.0 mL x 1 L/1000 mL = 0.1 L
moles of Pb(NO₃)₂ = 0.1 L x 1.00 mol/L = 0.1 mol
From the total ionic equation, we can see that 2 mol of LiBr reacts with 1 mol of Pb(NO₃)₂ to give 1 mol of PbBr₂ (solid product). The stoichiometric molar ratio is 2 mol LiBr/1 mol Pb(NO₃)₂ and we have 0.1 mol of each reactant (0.1 mol LiBr/0.1 mol Pb(NO₃)₂= 1). As 2 mol LiBr/mol Pb(NO₃)₂ > 1 mol LiBr/mol Pb(NO₃)₂, LiBr is the limiting reactant.
(f) From the total ionic equation, we know that 2 moles of LiBr produce 1 mol of PbBr₂. To determine the mass of solid product (PbBr₂) formed, we first multiply the stoichiometric ratio (1 mol PbBr₂/2 mol LiBr) by the actual number of moles of limiting reactant we have (0.1 mol):
moles of PbBr₂ = 0.1 mol LiBr x (1 mol PbBr₂/2 mol LiBr) = 0.05 mol PbBr₂
Finally, we convert the moles of PbBr₂ to gram by using the molar mass of the compound:
Molar mass PbBr₂ = 207.2 g/mol + (2 x 79.9 g/mol) = 367 g/mol
grams of PbBr₂ = 0.05 mol x 367 g/mol = 18.35 g
Which statement best defines the resistance of an electric circuit?
it limits the amount of electrical energy that can pass through a circuit.
It is the amount of electrical energy that is available in a circuit
It is the measurement of the rate of electrical energy in a circuit.
It describes how much electrical energy passes in a circuit.
Answer:
electric circuits can be dangerous
Explanation:
Answer:
The first one
it limits the amount of electrical energy that can pass through a circuit.
What will a child given a vaccine hopefully develop?
O A. Antibiotic Resistance
OB. Immunity
0
C. Mutages
D. Increased Growth
Answer:
B (immunity) is the answer
Acetylene gas is often used in welding torches because of the very high heat produced when it reacts with oxygen gas, producing carbon dioxide gas and water vapor. Calculate the moles of oxygen needed to produce of water. Be sure your answer has a unit symbol, if necessary, and round it to the correct number of significant digits.
Answer:
0.225 mol = 0.23 mol to 2 significant figures
Explanation:
Calculate the moles of oxygen needed to produce 0.090 mol of water
The equation of the reaction is given as;
2 C2H2 + 5 O2 --> 4 CO2 + 2 H2O
From the equation of the reaction;
5 mol of O2 produces 2 mol of H2O
x mol of O2 produces 0.090 mol of H2O
5 = 2
x = 0.090
x = 0.090 * 5 / 2
x = 0.225 mol
PLEASE HELP ME
If you start with 6 waters
going in during photosynthesis, how many waters are released during cellular respiration?
2
6
12
3
Answer:
Water is also a product of photosynthesis. This water is produced from the oxygen atoms in the carbon dioxide molecules. The oxygen molecules released into the atmosphere come exclusively from the original water molecules, not from the carbon dioxide molecules...
Hope this helps answer your question!
B r a i n l e i s t ?
For the reaction C + 2H2 → CH4, how many grams of hydrogen are required to produce 13.1 moles of methane, CH4 ?
Round your answer to the nearest tenth. If your answer is a whole number like 4, report the answer as 4.0
Answer:
7.0
Explanation:
Why does heating increase the speed at which a solute dissolves in water?
O A. It decreases the surface area of the solute.
B. It prevents the solute from cristallizing.
O c. It makes the water molecules move faster.
D. It raises the pressure of the water molecules.
Answer: C
Explanation:
It gives kinetic energy to the molecules and it breaks the bonds faster because they jiggle more
Please explain to me!!!
Answer:
nice handwrtting
Explanation:
Hydrocarbons are compounds that are composed of only carbon and hydrogen atoms. A hydrocarbon has a density of 2.59 g/L at STP. What is the molar mass of this hydrocarbon? Be sure to include units with your answer.
Answer:
58.0 g/mol
Explanation:
At STP, one mole occupies 22.4 liters. One mole of the hydrocarbon would have a mass of ...
(2.59 g/L)(22.4 L/mol) ≈ 58.0 g/mol
Answer:
58.0 g/molthe molar mass of this given hydrocarbonA bottle of viranin water contains 3500 mg of potassium in 591.5 mg of H2O. What is the concentration of potassium by mass percent
Answer: 085.5%
Explanation:
What is the edge length of a 377-g iron cube? (The density of iron is 7.86 g/cm^3, and the volume of a cube is equal to the edge length cubed.)
Answer:3.50 cm
Explanation:
Answer:
3.63cm
Explanation:
The mineral content of rocks helps to
classify them.
B
weigh them.
с
melt them.
D
find them.
Answer:
Explanation:
The rocks are composed of mineral grains combined in different ways and having various properties. Minerals are naturally occurring chemical compounds in which atoms are arranged in three-dimensional patterns.
This group of fungi forms spores in a round structure on the end of a hyphae
Answer:
Is zygote fungi an option??
Answer:
zygote fungi
Explanation:
i got the answer right
Heat will continue to move until the objects or areas have reached the same ______.
Answer: Thermal Equilibrium
Explanation:
Answer:
temperature
Explanation:
I think that's it i'm sorry if i'm wrong
24. The vaporization point of water is the same as its condensation point. True or False?
a. True
b. False
Answer:
pretty sure it's false
Explanation:
How many grams of O2 are formed from 13.34 moles of KClO3? Provide your final answer rounded to two decimal places.
2 KClO3 → 2 KCl + 3 O2
Answer:
640.32 g
Explanation:
2KClO₃ → 2KCl + 3O₂
First we convert KClO₃ moles to O₂ moles, using the stoichiometric coefficients:
13.34 mol KClO₃ * [tex]\frac{3molO_{2}}{2molKClO_{3}}[/tex] = 20.01 mol O₂Then we convert O₂ moles to grams, using its molar mass:
20.01 mol O₂ * 32 g/mol = 640.32 gSo 640.32 g of O₂ are formed from 13.34 moles of KClO₃.
List the 4 cell structures from largest to smallest
Answer: The smallest structure is the double helix while the largest is the chromosome.
2. G2 phase is the third stage in cellular division wherein the cell prepares itself for the M phase.
3. Interphase comprises of 3 phases, namely, G1 phase, G2 phase, and S phase.
4. Metaphase is known to take less amount of time to complete.
Explanation:
1. The double helix of the DNA or deoxyribonucleic acid, nucleosome, coil, supercoil, and the chromosomes are all linked to the DNA and they vary in their sizes. The nucleosome is known to be the basic unit of the eukaryotic chromosome that is composed of DNA coiled around the histones. The supercoils and coils indicate to the structures which are derived from the folding as well as wrapping of the structure of the DNA. The chromosome refers to the thread-like structure which is made up of nucleic acid and is observed in the nucleus of the living organisms.
2. Cell cycle refers to the cellular division of the cell; it is the series of events which occurs within a cell that results in duplication of the DNA or deoxyribonucleic acid as well as division of the cytoplasm and other organelles in order to generate two daughter cells. This cycle comprises of 4 phases, namely, G1, S, G2, and M phase.
The cell enters the G1 phase wherein the cell synthesizes the proteins as well as mRNA or messenger ribonucleic acid in preparation for the next upcoming phases which lead to mitosis. Next stage is the S phase wherein the synthesis of DNA takes place.
G2 phase is the next phase wherein the cell prepares itself by allowing it to grow as well as generate new proteins needed for the next phase called M phase. Mitosis is the final stage wherein the two identical daughter cells are made from one parent cell.
3. The cell cycle is broadly segregated into 3 phases, namely, interphase, M phase, and cytokinesis. Interphase is the longest stage of the cellular cycle and it comprises of 3 phases, G1 phase, S, and G2 phase. There is a G0 phase or quiescent phase. During the G1 phase, the cell prepares itself for the next phases of cell cycle, S phase involves synthesis of DNA, and G2 is the production of new proteins needed for the M phase.
4. During the mitotic phase, the parental cell segregates and produces 2 identical daughter cells. This phase is further segregated into prophase followed by metaphase, anaphase, and finally telophase. During metaphase, the chromosomes align themselves onto the equatorial or metaphase plate and the centrosomes prepare to segregate the sister chromatids. This phase takes only about 4% of the time needed to finish the entire cell cycle.
Explanation:
Liquid octane CH3CH26CH3 will react with gaseous oxygen O2 to produce gaseous carbon dioxide CO2 and gaseous water H2O. Suppose 2.3 g of octane is mixed with 12.4 g of oxygen. Calculate the minimum mass of octane that could be left over by the chemical reaction. Round your answer to 2 significant digits.
Answer: Octane will be used completely.
Explanation:
To calculate the moles :
[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex]
[tex]\text{Moles of octane}=\frac{2.3g}{114g/mol}=0.0202moles[/tex]
[tex]\text{Moles of oxygen}=\frac{12.4g}{32g/mol}=0.388moles[/tex]
The balanced chemical reaction will be
[tex]2C_8H_{18}+25O_2(g)\rightarrow 16CO_2(g)+18H_2O(g)[/tex]
According to stoichiometry :
2 moles of octane require = 25 moles of [tex]O_2[/tex]
Thus 0.0202 moles of octane will require=[tex]\frac{25}{2}\times 0.0202=0.2525moles[/tex] of [tex]O_2[/tex]
Thus octane is the limiting reagent as it limits the formation of product and [tex]O_2[/tex] is the excess reagent.
Thus octane will be used completely.
Fires mostly frequently occur in the kitchen true or false
HELP ASAP
Which group of elements is listed in order of decreasing size? O oxygen, nitrogen, carbon, boron O xenon, krypton, argon, neon O carbon, silicon, germanium, tin O lead, thallium, mercury, gold
Answer:
oxygen, nitrogen, carbon, boron
Explanation:
A reaction that proceeds by first-order irreversible kinetics is oxidizing chemical A in a wastewater treatment basin with a mean residence time of 1.5 hours. The reaction rate constant is The basin is unbaffled and may be characterized as two completely mixed tanks in series. If the steady-state influent concentration is 30 mg/l, find the effluent concentration. If baffles are placed in the basin so that the basin may be characterized as four completely mixed tanks in series, and the mean residence time remains constant, find the effluent concentration.
This question is incomplete, the complete question is;
A reaction that proceeds by first-order irreversible kinetics is oxidizing chemical A in a wastewater treatment basin with a mean residence time of 1.5 hours. The reaction rate constant is 2.0 Hr-1.The basin is unbaffled and may be characterized as two completely mixed tanks in series. If the steady-state influent concentration is 30 mg/l, find the effluent concentration.
If baffles are placed in the basin so that the basin may be characterized as four completely mixed tanks in series, and the mean residence time remains constant, find the effluent concentration.
Answer:
a) (two completely mixed tanks in series) the find the effluent concentration is 4.8 [tex]\frac{mg}{l}[/tex]
b) (four completely mixed tanks in series) find the effluent concentration is 3.2 [tex]\frac{mg}{l}[/tex]
Explanation:
Given the data in the question;
we can determine the effluent concentration of two completely mixed tanks in series for first order irreversible reaction using the following equation;
C = Co ( 1 / ( 1 + K[tex]\frac{t}{n}[/tex] )ⁿ
t is the mean hydraulic residence time for two completely mixed tanks in series ( 1.5 hr)
Co is initial concentration of the influent ( 30 [tex]\frac{mg}{l}[/tex] )
C is final concentration of effluent,
n is the number of tanks series ( 2)
k is rate constant for the given first order reaction( 2[tex]\frac{1}{hour}[/tex] )
so we substitute
C = 30 [tex]\frac{mg}{l}[/tex] ( 1 / ( 1 + 2[tex]\frac{1}{hour}[/tex] . [tex]\frac{1.5}{2}[/tex] )²
C = 30 [tex]\frac{mg}{l}[/tex] × ( 1/2.5)²
C = 30 [tex]\frac{mg}{l}[/tex] × 0.16
C = 4.8 [tex]\frac{mg}{l}[/tex]
Therefore, (two completely mixed tanks in series) the find the effluent concentration is 4.8 [tex]\frac{mg}{l}[/tex]
b)
using;
C = Co ( 1 / ( 1 + K[tex]\frac{t}{n}[/tex] )ⁿ
t is the mean hydraulic residence time for two completely mixed tanks in series ( 1.5 hr)
Co is initial concentration of the influent ( 30 [tex]\frac{mg}{l}[/tex] )
C is final concentration of effluent,
n is the number of tanks series ( 4)
k is rate constant for the given first order reaction( 2[tex]\frac{1}{hour}[/tex] )
so we substitute
C = 30 [tex]\frac{mg}{l}[/tex] ( 1 / ( 1 + 2[tex]\frac{1}{hour}[/tex] . [tex]\frac{1.5}{4}[/tex] )⁴
C = 30 [tex]\frac{mg}{l}[/tex] × ( 1/1.75)²
C = 30 [tex]\frac{mg}{l}[/tex] × 0.107
C = 3.2 [tex]\frac{mg}{l}[/tex]
Therefore, (four completely mixed tanks in series) find the effluent concentration is 3.2 [tex]\frac{mg}{l}[/tex]
What is the mole ratio between H2O and O2
With the given chemical compounds, what is the balanced chemical equation when lit with fire?
Answer:
Russia es el mejor pais? Vladimir Putin, es el mejor presidente del mundo
Sulfuric acid, H 2 S O 4 , is an important industrial chemical, typically synthesized in a multi-step process. What is the percent yield if a batch of H 2 SO 4 has a theoretical yield of 3.9 kg, and 2.8 kg are obtained at the end of the process
Answer:
71.8%
Explanation:
The percent yield of a process or a chemical reaction is calculated as:
percent yield = actual yield/theoretical yield x 100%
From the problem we have:
theoretical yield = 3.9 kg
actual yield = 2.8 kg
Thus, we calculate the yield of H₂SO₄ production as follows:
percent yield = (2.8 kg/3.9 kg) x 100 = 71.79 % ≅ 71.8%
Racecar driver Keimesha was in a race and accelerated from rest to 39 m/s by the time she reached the finish line. Keimesha’s car moved in a straight line and traveled from the starting line to the finish line in 6.0 seconds. What was the acceleration of the dragster?
Answer:
the acceleration of the racecar is 6.5 m/s²
Explanation:
Given;
initial velocity of the racecar, u = 0
final velocity of the racecar, v = 39 m/s
time of motion, t = 6.0 s
The acceleration of the racecar is calculated as;
[tex]a = \frac{v-u}{t} \\\\a = \frac{39-0}{6} \\\\a = \frac{39}{6} \\\\a = 6.5 \ m/s^2[/tex]
Therefore, the acceleration of the racecar is 6.5 m/s²
1. How many grams are there in 1.5 x 10^25 molecules of CO2?
Answer: 1.1 kg
Explanation:
Mw CO2 is 44g —> 6.02214076*10^23 molecules
1.5*10^25 molecules —> 1.1 kg
Which of the following does not describe a chemical property?
A. Gasoline burns.
B. Gold does not react with oxygen.
C. Bleach is poisonous when swallowed.
D. Lead is more dense than gold.
The one that does not describe a chemical property is bleach is poisonous when swallowed. The correct options are C.
What are chemical properties?Chemical properties are those properties that show the reactivity of an element. These chemical properties are pH, chemical stability, reactivity, radioactive decay, flammability, toxicity, etc.
Gasoline is a chemical compound, its burning will be a chemical property because it shows how it reacts when it comes in contact with another chemical.
Gold is a pure element, its reactivity tendency is a chemical property, and it is not reactive with oxygen. Density is also a property of an element. And lead is denser than gold, which will show a chemical property.
Thus, the correct options are C. Bleach is poisonous when swallowed.
To learn more about chemical properties, refer to the link:
https://brainly.com/question/5186976
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How much heat energy is required to raise the temperature of 0.362 kg of copper from 23.0 ∘C to 60.0 ∘C? The specific heat of copper is 0.0920 cal/(g⋅∘C) .
Answer:
83
Explanation:
23+60=83