Answer:
25 gram
Explanation:
the minimum amount of the reactant needed is equal to the mass of the product because of the law of conservation of mass ok
Find the concentration of Pb2 (aq) in ppm by mass of a 1.13 L sample of contaminated water that was assayed by adding NaI(s) and obtaining 55.1x10-3 g of PbI2(s) precipitate. Assume that Pb2 (aq) is completely precipitated as PbI2(s). The molar mass of PbI2(s) is 461.01 g/mol. Assume that the density of the solution is 1.00 kg/L. Give the answer with 3 or more significant figures.
Answer:
22.1 ppm
Explanation:
The equation of the reaction is;
Pb2+ (aq) + 2NaI(s) ------>PbI2(s) + 2 Na^2+
Mass of precipitate = 55.1x10-3 g
Number of moles of precipitate = 55.1x10-3 g/461.01 g/mol = 1.2 * 10^-4 moles
1 mole of Pb2+ yields 1 mole of PbI2
Hence 1.2 * 10^-4 moles of Pb2+ also yields 1.2 * 10^-4 moles of PbI2.
Hence mass of Pb2+ present = 1.2 * 10^-4 moles * 207 g/mol = 0.025 g or 25 mg
Mass of solution = Density of solution * volume of solution
Mass of solution = 1.00 kg/L * 1.13 L
Mass of solution = 1.13 Kg
Concentration in mg/Kg(ppm) = mass of solute/mass of solution
= 25 mg/1.13 kg
= 22.1 ppm
Brainiest and 10 points
Which has a HIGHER frequency?
A. Orange light
B. Blue light
Answer:
A. Orange light
Explanation:
According to the band spectrum of white light ( ROYGBIV )
Answer:
I think it blue light is higher
Two airplanes are flying in the sky in such a way that the gravitational attractions between them decreases. The planes must be flying:
A.
away from each other.
B.
next to each other at the same speed.
C.
towards each other.
D.
faster than the speed of sound.
Two airplanes are flying in the sky in such a way that the gravitational attractions between them decreases. The planes must be flying away from each other. Hence option A is correct.
What is gravitational attraction?Gravitational attraction is defined as a basic interaction that pulls everything with mass or energy in the same direction. All objects are subject to gravitational interactions, the strength of which is directly inversely proportional to the product of their masses. The size of an object and the separation between the objects have an impact on gravity.
In order to reduce the gravitational pull, two planes are flying in the sky. There must be a directionality between the aircraft. No matter what is in between the two bodies, there will still be gravitational pull. As a result, even if the medium between the two bodies changed, the gravitational force between them would not.
Thus, two airplanes are flying in the sky in such a way that the gravitational attractions between them decreases. The planes must be flying away from each other. Hence option A is correct.
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Sodium hydroxide, NaOH, is a strong base that is sometimes used as a cleaning agent since it can be used to dissolve proteins, grease, oils, and fats. Rank the following in increasing order of their molarity. Rank from lowest to highest.
a. 6.625 g NaOH dissolved in 250. mL of water
b. 63.0 g of NaOH dissolved in 1.00 L of water
c. 8.00 g of NaOH dissolved in 500. mL of water
d. 0.0530 of NaOH in 100 mL of water
Answer:
Rank from lowest to highest - c<a<d<b
Explanation:
Molarity is basically the moles of the solute dissolved in a solvent. Molar mass of NaOH = 39.997 g/mol
a) 6.625 g NaOH dissolved in 250. mL of water
Molarity = 6.625 grams */( 0.250 *39.997) g/mol = 0.66
b) 63.0 g of NaOH dissolved in 1.00 L of water
Molarity = 63 grams */( 1 *39.997) g/mol = 1.575
c) 8.00 g of NaOH dissolved in 500. mL of water
Molarity = 8 grams */( 0.5 *39.997) g/mol = 0.331
d) 0.0530 of NaOH in 100 mL of water = 0.53
Rank from lowest to highest - c<a<d<b
When fuels are burned, the chemical energy that is released can be used to generate another form of energy, such as heat, light,motion,or electricity. This is called
Answer: When fuels are burned, the chemical energy that is released can be used to generate another form of energy, such as heat, light, motion, or electricity. This is called combustion.
Explanation:
The chemical energy present in fuels actually releases when these fuels are burned or by combustion.
Hence when fuels are burned, the chemical energy that is released can be used to generate another form of energy, such as heat, light, motion, or electricity. This is called combustion.
For example, gasoline present in vehicles burns and undergoes chemical change which is then converted into thermal energy. This thermal energy then converts into mechanical energy due to which car moves.
Thus, we can conclude that when fuels are burned, the chemical energy that is released can be used to generate another form of energy, such as heat, light, motion, or electricity. This is called combustion.
Acids and bases are chemical molecules with very different characteristics.
a. True
b. Fasle
Answer:
TRUE ,hope it helped you
Explanation:
Magnesium metal reacts with a solution of silver nitrate in a single-replacement reaction, producing aqueous magnesium
nitrate and silver metal.
If a reaction starts with 0.480 mol Mg, how many moles of silver are produced?
You must show a proper set up for the calculation, the answer with a proper unit, and
the proper significant figures.
Answer:
0.960 mol of Ag
Explanation:
Mg(s) + 2AgNO3(aq) → Mg(NO3)2(aq) + 2Ag(s)
1.00 mol of Mg ---- 2.00 mol of Ag
0.480 mol of Mg ---- x
x = (0.480×2)/1 = 0.960 mol of Ag
7. water, when heated, changes into this
Answer:
We learned that waterhas three states: ice is the solid state, watervapor is the gaseous state, and wateris the liquid state. When water is heatedit evaporates, which means it turns into watervapor and expands. Secondly, does water expand when heated?
Explanation:
Construct a Lewis structure for hydrogen peroxide, H2O2, in which each atom achieves a stable noble-gas electron configuration. Draw the molecule by placing atoms on the grid and connecting them with bonds. Include all lone pairs of electrons.
Answer:
See explanation and image attached
Explanation:
Hydrogen peroxide is made up of two atoms of hydrogen and two atoms of oxygen as shown in the image attached.
The two oxygen atoms are joined together by a single covalent bond and each of the oxygen atoms are bonded to one hydrogen atom each.
There are two lone pairs on each of the oxygen atoms.
The Lewis(dot) structure for hydrogen peroxide is shown in the image attached to this answer.
El butano, C4H10, se quema en presencia de oxígeno gas, O2, y se produce dióxido de carbono, CO2, y agua. ¿Cuántos kg de CO2 se obtendrán al quemarse 12 kg de butano?
Answer:
don't know really and don't know at alll
How many grams of O2 can be produced from 3 moles KCIO3-
Answer:
In the question the mass has two significant figures; thus the mass of O2 released would be 4.0 g (two significant figures). 122.55 g of KClO3 yields 3*32 g of O2
Explanation:
Which equation is correctly balanced?
Answer:
When the moles of the reactant is equal to the mole of the product.
Explain why the ability of PLP to catalyze an amino acid transformation is greatly reduced if the OHOH substituent of pyridoxal phosphate is replaced by OCH3OCH3.
Answer:
Following are the responses to the given question:
Explanation:
In the given question the OH could be generated as the H-bond with both the N (nitrogen), which is used to place its N as the partially positive value(+). It is used to simplifies the addition for either its AA with the imine C. In the above H-bond, the w N is not required as the possibility to use the OCH3
In the ground state, the valence electrons of a krypton atom are found in
1. The first shell
2. The outermost shell
3. Both the nucleus and the first shell
4. Both the first shell and the outermost shell
Answer: 2. The outermost shell
Explanation:
In an elements ground state, its electrons have the least amount of energy that they could have so they stay in their shells. When Krypton is in this state therefore, its valence electrons will stay in the outermost shell.
As Krypton has a total of 36 electrons in this state, there will be 8 valence electrons and they will all be in the outer shell.
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which of the following has the largest atomic radius?
Al
B
Ca
N
Answer:
Im not sure if im right but i think its Ca
Explanation:
A heavy brick weighs more than a fluffy cushion, but the cushion takes up more space. Which object has more matter?
Answer:
The brick has more matter because it has more mass.
Explanation:
Please someone help me!
I need this done ASAP *URGENT*
I Need this done before Thursday or Friday because Friday is my last day of school so please finish this today!
Best answer gets BRAINLIEST
PLEASE HURRY AND ANSWER ALL QUESTIONS CORRECTLY
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What’s the difference worksheet
Atoms,molecules,elements and compounds
PLEASE PLEASE PLEASE PLEASE PLEASEEEEEEE ANSWER THIS I only have TWO days of school left! And I need this done quickly
To solve this we must be knowing each and every concept related to chemical formula. Therefore, in the above given ways the chemical formula for the molecule can be written.
What is chemical formula?A chemical formula is a scientific notation that uses atomic symbol and numerical subscripts to represent the number and types of elements contained in a molecule. A chemical formula seems to be a concise written description of an existing three-dimensional molecule.
A chemical formula characterizes a material to the atomic level. There are three sorts of chemical formulas: empirical, molecular, and structural.
The chemical formula for the given molecules are:
2. H[tex]_2[/tex]O
3. O[tex]_3[/tex]
4. H[tex]_2[/tex]
5. CO[tex]_2[/tex]
6. CO
7. NO[tex]_2[/tex]
8. CH[tex]_4[/tex]
Therefore, in the above given ways the chemical formula for the molecule can be written.
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A mixture of 0.224 g of H2, 1.06 g of N2, and 0.834 g of Ar is stored in a closed container at STP. Find the volume (in L) of the container, assuming that the gases exhibit ideal behavior.
Answer: The volume of given container is 3.83 L.
Explanation:
Given: Mass of [tex]H_{2}[/tex] = 0.224 g
Mass of [tex]N_{2}[/tex] = 1.06 g
Mass of Ar = 0.834 g
Since, moles is the mass of a substance divided by its molar mass. Therefore, moles of given substances present in the mixture are as follows.
Moles of [tex]H_{2}[/tex] are:
[tex]Moles = \frac{mass}{molar mass}\\= \frac{0.224 g}{2 g/mol}\\= 0.112 mol[/tex]
Moles of [tex]N_{2}[/tex] are:
[tex]Moles = \frac{mass}{molar mass}\\= \frac{1.06 g}{28 g/mol}\\= 0.038 mol[/tex]
Moles of Ar are:
[tex]Moles = \frac{mass}{molar mass}\\= \frac{0.834 g}{40 g/mol}\\= 0.021 mol[/tex]
Total moles = (0.112 + 0.038 + 0.021) mol = 0.171 mol
Now, using ideal gas equation the volume is calculated as follows.
PV = nRT
where,
P = pressure
V = volume
n = no. of moles
R = gas constant = 0.0821 L atm/mol K
T = temperature
Substitute the values into above formula as follows.
[tex]V = \frac{nRT}{P}\\= \frac{0.171 mol \times 0.0821 L atm/mol K \times 273 K}{1 atm}\\= 3.83 L[/tex]
Thus, we can conclude that the volume of given container is 3.83 L.
An unknown compound (152 mg) was dissolved in water to make 75.0 mL of solution. The solution did not conduct electricity and had an osmotic pressure of 0.328 atm at 27°C. Elemental analysis revealed the substance to be 78.90% C, 10.59% H, and 10.51% O. Determine the molecular formula of this compound.
Answer:
The molecular formula of the compound is C10H16O.
Explanation:
Based on the given information, the mass of an unknown compound is 152 mg or 0.152 g, which was dissolved to produce 75 ml of solution.
The osmotic pressure of the solution is 0.328 atm at 27 degrees C or 300 K.
The formula of osmotic pressure is,
P = CRT
Now putting the values in the formula we get,
0.328 = C*0.0821*300
C = 0.013317
C = (mass/molecular mass) * (1000/volume of solution in ml)
0.013317 = (0.152/Molecular mass) * (1000/75)
Molecular mass = 152.186
C mass = 152.186 * 0.789 = 120.07 grams
C mole = 120.07/12 = 10
H mass = 152.186 * 0.1059 = 16.11 grams
H mole = 16.11/1 = 16
O mass = 152.186 - 120.07 - 16.116 = 16 grams
O mole = 16/16 = 1
Thus, the molecular formula of the compound will be,
C10H16O
Calculate the mass of sucrose needed to prepare a 2000 grams of 2.5% sucrose solution.
Explanation:
[tex] = 2.5\% \times 2000 \\ = \frac{2.5}{100} \times 2000 \\ = 50 \: g[/tex]
I need help with my chemistry but you can only choose one correct answer
Answer:
Explanation:
photosynthesis
the given chemical reaction is photosynthesis.
During photosynthesis carbon dioxide absorbed by plants reacts with water in presence of sunlight to give glucose and oxygen.
200 grams of iron (III) chloride reacts with ammonium carbonate [(NH4)2CO3] in the following equation.
FeCl3 + (NH4)2CO3 ---------> NH4Cl + Fe2(CO3)3
The number of grams of ammonium chloride (NH4Cl) that will be produced is ___ grams.
a
395
b
181
c
198
d
339
Answer:
[tex]FeCl₃ + (NH₄)₂CO₃ → NH₄Cl + Fe₂(CO₃)₃[/tex]
first balance the chemical equation
first balance the chemical equation[tex]2FeCl₃ + 3(NH₄)₂CO₃ → 6NH₄Cl + Fe₂(CO₃)₃[/tex]
2FeCl₃=2*162=324g
6NH₄Cl=6*53.5=321g
324 g of FeCl₃ gives 321 g of NH₄Cl
200g of FeCl₃ gives 321/324*200=198.14 g of NH₄Cl
in nearest value it is 198g/mole
The number of grams of ammonium chloride (NH4Cl) that will be produced is C.198___ grams.To double-check a chemical in lab before using it, sniff near the opening of the container, true or false?
Compound X has the molecular formula C6H10. X decolorizes bromine in carbon tetrachloride. X also shows IR absorption at about 3300 cm-1 . When treated with excess hydrogen and a nickel catalyst, X yields 2-methylpentane. The most likely structure for X is:
Answer:
The correct answer is - option D. (check image)
Explanation:
Alkynes and alkenes both decolorized bromine in carbon tetrachloride. The absorption of the IR at about 3300 cm-1 for the X here that are found in the terminal alkynes absorption range only. In presence of excess hydrogen and a nickel catalyst, x gives the 2-methyl pentane.
The most likely structure for X is: CH3-CH3-ch-CH2-C≡CH
A compound having double and triple bonds is called alkenes and alkynes. The most likely structure of the compound will be 2 -methyl -4- hexyne.
What is the molecular formula?
The molecular formula represents the chemical atomic proportions of the compound or the molecule through the symbols, and numbers.
Bromine is decolorized by the alkynes and alkenes. The absorption range is followed by the terminal alkynes and in excess hydrogen yields 2-methyl pentane.
Therefore, 2 - methyl - 4 - hexyne is most likely to be X.
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7 grams of oxygen gas is reacted with excess C4H8. How many grams of CO2 gas at STP are produced?
The pressure of a gas is 1.0 atm, the volume is 3.0 L, and the temperature is 200 K. A chemist changes one factor while keeping another constant so that the new pressure is 2.0 atm. Which of the following could be the new conditions?
The final volume is 6.0 L, while temperature is kept constant.
The final temperature is 100 K, while volume is kept constant.
The final volume is 4.0 L, while temperature is kept constant.
The final temperature is 400 K, while volume is kept constant.
Answer: The correct answer is actually: The final temperature is 400 K, while volume is kept constant.
Explanation: Got it right on test!
A sealed container contains a sample of air. The average speed of a hydrogen gas molecule in this container is 2222 meters per second. What is the average speed of a nitrogen gas molecule, in meters per second , in the container
Answer:
fhkigfkh mlfhg,hgljh
Explanation:
l,dlflfk,jhm,gkhmtyhm,;tgjnh
About how long did it take for this population to reach the carrying capacity of this habitat
Answer:100
Explanation:
It is defined as a push or pull that starts, stops or changes the direction of a moving object. *
Answer:
A force is a push or pull that can cause an object to move, stop, or change speed or direction.
I think it's Force.
A Force is any push or pull that causes an object to move, stop, or change speed or direction.How do isotopes of the same atom react chemically? How do isotopes of the same atom compare in size?
Atoms of the same elements differing in the number of neutrons in their nuclei are known as isotopes. Thus, isotopes of an element have the same atomic number but different atomic mass number. Isotopes of an element have similar chemical properties but different physical properties.