A natural element consists of two isotopes: Cl-35 and Cl-37. The composition of these two isotopes differs by:
Answer:
There are no options in this question, however, it can be answered based on general understanding
- The number of neutrons each isotope contain
Explanation:
Isotopes are atoms of an element with the same atomic number or number of protons but different mass number/atomic masses. Since isotopes have same proton numbers, they have similar chemical behavior or identity.
However, difference in atomic mass or mass number of the same atomic number indicates that the number of neutrons each isotope contain differs from one another. Hence, in two isotopes of chlorine given as follows: Cl-35 and Cl-37, the NUMBER OF NEUTRONS in each atom differentiates the two isotopes.
Cl-35 contains 18 neutrons while Cl-37 contains 20 neutrons.
PLEASE HELP!!
this is on USAtestprep
a)
b)
c)
d)
What is the mass grams that are in 3.52 × 10²⁵ molecules of I₂
Answer:
As you know, one mole of any substance contains exactly
6.022
⋅
10
23
molecules of that substance - this is known as Avogadro's number.
Notice that you're dealing with more than
6.022
⋅
10
23
molecules of carbon dioxide, which means that you'll also be dealing with more than one mole of the compound.
More specifically, you'll have
1.5
⋅
10
26
molecules
⋅
1 mole CO
2
6.022
⋅
10
23
molecules
=
2.491
⋅
10
2
moles CO
2
Now, a substance's molar mass tells what the mass of one mole of that substance is. In carbon dioxide's case, its molar mass is equal to
44.01 g/mol
, which means that every mole of
CO
2
will have a mass of
44.01 g
.
In your case,
2.491
⋅
10
2
moles of
CO
2
would have a mass of
2.491
⋅
10
2
moles CO
2
⋅
44.01 g
1
mole CO
2
=
109.63 g
Rounded to two sig figs, the number of sig figs you have for the number of molecules of
CO
2
, the answer will be
m
C
O
2
=
110 g
What volume of each solution contains 0.14 mol of KCl? Express your answer using two significant figures.
1.8 M KCl
Answer:
Solution given:
1 mole of KCl[tex]\rightarrow [/tex]22.4l
1 mole of KCl[tex]\rightarrow [/tex]74.55g
we have
0.14 mole of KCl[tex]\rightarrow [/tex]74.55*0.14=10.347g
74.55g of KCl[tex]\rightarrow [/tex]22.4l
10.347 g of KCl[tex]\rightarrow [/tex]22.4/74.55*10.347=3.11litre
volume of each solution contains 0.14 mol of KCl contain 3.11litre.
1 mol of any gas contains 22.4L of volume at STP
Moles of KCl=0.14Volume of KCl:-
0.14(22.4)3.14LStibnite, Sb2S3, is a dark gray mineral from which antimony metal is obtained. What is the mass percent of antimony in the sulfide? If you have 1.00 kg of an ore that contains 10.6% antimony, what mass of Sb2S3 (in grams) is in the ore?
Answer:
duw8 Wert gsi
Explanation:
pues pues y 8y1rcuecisscfjfj3eoeu xv cihskdkkd HD jekifeuifkeñ elijo eh fh FC eh SSH DJ djdvheshdhs
The mass percent of antimony in the sulfide is 71.7% and the mass of Sb2S3 is 0.148 g.
What is mass percent?Mass percent is defined as a way of expressing a concentration or describing a component in a particular mixture.
To calculate the mass percent of an element in a compound, divide the mass of the element in 1 mole of the compound by the molar mass of the compound and multiply the result by 100.
Mass percent = Mass of chemical / Total mass of compound x 100
Mass of ore = 10 kg
% antimony in ore = 10.6%
= 10.6 / 100 = 0.106 g
Mass of antimony = 0.106 g
Mass percent = Mass of antimony / Mass of stibnite x 100
71.7% = 0.106 / X x 100
X = 0.106 x 1000 / 71.7 x 1000
= 106 / 717 = 0.148 g
Thus, the mass percent of antimony in the sulfide is 71.7% and the mass of Sb2S3 is 0.148 g.
To learn more about mass percent, refer to the link below:
https://brainly.com/question/5840377
#SPJ2
In the reaction HCI + NH4OH --> NH4CI+H2O, which compound has an element ratio of 1:4:1?
H2O
NH4Cl
HCI
ΝΗ4ΟΗ
The compound in this reaction which is having the elemental ratio of 1:4:1 is NH₄Cl where nitrogen and chlorine are of one mole each with 4 hydrogens.
What is elemental ratio?Elemental ratio of a compound is the ratio of number of atoms of each elements in that compound. The elemental ratio can be determined from the molecular formula of compounds.
The given reaction is a double displacement reaction. Here, the Cl group is replaced to the ammonia and OH group is replaced to the water. Thus, two species is replaced in the reaction.
In NH₄Cl, there are one nitrogen, 4 hydrogens and one chlorine atom. Therefore, the elemental ratio of the compound is 1:4:1. The elemental ratio of water is 2:1 and HCl is 1:1 and that in NH₄OH is 1:5:1. Hence, option b is correct.
To find more on elemental ratio, refer here:
https://brainly.com/question/17613193
#SPJ2
A hypothetical atom has four unequally spaced energy levels in which a single electron can be found. Suppose a collection of the atoms are excited to the highest of the four levels. What is the maximum number of unique spectral lines that could be measured as the atoms relax and return to the lowest, ground state
Answer:
[tex]X=6[/tex]
Explanation:
From the question we are told that:
Energy levels [tex]n=4[/tex]
Generally, the equation for spectral lines is mathematically given by
[tex]X=\frac{n(n-1)}{2}[/tex]
[tex]X=\frac{4(4-1)}{2}[/tex]
[tex]X=6[/tex]
When a solute is dissolved in water, it forms……
Answer:
an aqueous species is the answer
. Which of the following statement is not related to a chemical reaction ? A. New substances are formed B. Atoms of the elements transform into atoms of other elements C. The properties of the new substances will be different D. There will be bond breaking and bond forming
Answer:
the answer should be B because elements do not tranform into other elements in a chemical reaction
am I right please?
What is the name of the compound shown below?
A. 2-pentene
B. 1-propene
C. 2-propene
D. 1-pentene
The name of the compound shown below is 1- pentene. The correct answer is option D.
A compound is a substance made up of two or more different elements chemically bonded together in a fixed ratio.
1-pentene is an unsaturated hydrocarbon with the chemical formula [tex]\rm C_5H_{10}[/tex]. It is an alkene, which means it contains a carbon-carbon double bond.
The structure of 1-pentene is characterized by a chain of five carbon atoms (pentane) with one double bond between the first and second carbon atoms. The double bond causes the molecule to have a planar structure, with all atoms lying in the same plane. The remaining three carbon atoms in the chain are each bonded to two hydrogen atoms.Therefore, option D. 1-pentene is the name of the compound shown.
Learn more about compound here:
https://brainly.com/question/14117795
#SPJ6
150 mL of 0.25 mol/L magnesium chloride solution and 150 mL of 0.35 mol/L silver nitrate solution are mixed together. After reaction is completed; calculate the concentration of nitrate ions in solution. Assume that the total volume of the solution is 3.0 x 10^2 mL
Answer:
[tex]0.175\; \rm mol \cdot L^{-1}[/tex].
Explanation:
Magnesium chloride and silver nitrate reacts at a [tex]2:1[/tex] ratio:
[tex]\rm MgCl_2\, (aq) + 2\, AgNO_3\, (aq) \to Mg(NO_3)_2 \, (aq) + 2\, AgCl\, (s)[/tex].
In reality, the nitrate ion from silver nitrate did not take part in this reaction at all. Consider the ionic equation for this very reaction:
[tex]\begin{aligned}& \rm Mg^{2+} + 2\, Cl^{-} + 2\, Ag^{+} + 2\, {NO_3}^{-} \\&\to \rm Mg^{2+} + 2\, {NO_3}^{-} + 2\, AgCl\, (s)\end{aligned}[/tex].
The precipitate silver chloride [tex]\rm AgCl[/tex] is insoluble in water and barely ionizes. Hence, [tex]\rm AgCl\![/tex] isn't rewritten as ions.
Net ionic equation:
[tex]\begin{aligned}& \rm Ag^{+} + Cl^{-} \to AgCl\, (s)\end{aligned}[/tex].
Calculate the initial quantity of nitrate ions in the mixture.
[tex]\begin{aligned}n(\text{initial}) &= c(\text{initial}) \cdot V(\text{initial}) \\ &= 0.25\; \rm mol \cdot L^{-1} \times 0.150\; \rm L \\ &= 0.0375\; \rm mol \end{aligned}[/tex].
Since nitrate ions [tex]\rm {NO_3}^{-}[/tex] do not take part in any reaction in this mixture, the quantity of this ion would stay the same.
[tex]n(\text{final}) = n(\text{initial}) = 0.0375\; \rm mol[/tex].
However, the volume of the new solution is twice that of the original nitrate solution. Hence, the concentration of nitrate ions in the new solution would be [tex](1/2)[/tex] of the concentration in the original solution.
[tex]\begin{aligned} c(\text{final}) &= \frac{n(\text{final})}{V(\text{final})} \\ &= \frac{0.0375\; \rm mol}{0.300\; \rm L} = 0.175\; \rm mol \cdot L^{-1}\end{aligned}[/tex].
2. An ion is a charged particle that is formed when
a. An atom gains electrons
b. An atom loses electrons
c. Both A and B
d. None of the above
The correct answer is option c. Both A and B: An ion is a charged particle that is formed when an atom gains electrons or an atom loses electrons.
First you need to know the definition of ion. An ion is a molecule or atom that has a positive or negative electrical charge.
That is, an ion is an atom whose electric charge is not neutral. This charged particle can be positive or negative.
Ionization is the chemical or physical process by which ions are produced. In this process, negatively charged ions are produced by gaining electrons and are known as anions.
The positively charged are produced by the loss of electrons and are known as cations.
In summary, an ion is a charged particle that is formed when an atom gains electrons or an atom loses electrons, and they are known as cations and anions respectively.
The correct answer is both A and B.
Learn more about ions:
https://brainly.com/question/13692734?referrer=searchResults
PLEASE HELP ASAP!!!
Answer:
I don't know What can I do.
If Sterling silver is 90.0% silver and 10.0% copper, what is the maximum amount of Sterling silver that can be made if you have 48.3 grams of silver metal and an unlimited amount of copper
Answer:
[tex]x=54g[/tex]
Explanation:
From the question we are told that:
Content of Sterling silver:
Let x be sterling silver
Silver [tex]S=0.9x[/tex]
Copper [tex]C=0.1x[/tex]
Total silver available [tex]T=48.3[/tex]
Generally the equation for Total amount to be made is mathematically given by
[tex]T=\frac{x*90}{100}[/tex]
[tex]x=\frac{48.3*100}{90}[/tex]
[tex]x=54g[/tex]
how is the akin of frog similar to a fish
Answer:
Have you ever touched a fish? Most fish will feel a bit rough - due to their scales. Some, like sharks, will feel like sandpaper. Even fish with small, smoother scales will feel a bit like that. Amphibians don’t have scales, and most species will be wet to some degree - they have to keep their skin moist or they’ll die. A few groups, like toads and newts, have rougher skin, which is heavier and thicker, which allows them to retain moisture better away from water.
Functionally, the big thing about amphibian skin is that it is semi-permeable. Amphibians can breathe through their skin - all amphibians can get some oxygen through their skin, but some species of salamanders get all their oxygen that way - they have no lungs or gills. The skin can also allow water in - sort of like a paper towel. The bad thing is that other chemicals can pass through the skin, too - pollutants and other chemicals tend to affect amphibians far more than they do other groups.
Amphibians also shed their skin - fish do not. People don’t tend to see frogs shedding their skin often, though, since they eat it to regain nutrients and other resources in the skin.
Finally, since amphibian skin offers no defense against predators in the way that scales do, and limited barrier against disease the way non-amphibian skin does (shedding helps), the skin of many amphibians contain toxins, and some of them have anti-fungal properties (typically due to symbiotic bacteria). Many species have evolved chemical defenses in the skin, while others have glands that produce toxins that can be secreted outside of the skin.
The skin can withstand dessication more than the fish.
They have moist skin used as respiratory surface during deep sleep / hibernation.
They have moist skin due to secretion of mucus by glands under the skin.
please mark me as brainliest
Cho các quá trình và số liệu sau:
C(d,s) ⭢ C (g,s) (1) : ΔH0298 = - 1,9 kJ
ΔG0298 = - 2,87 kJ
C(g,s) + O2 (k) ⭢ CO2 (k) (2): ΔH0298 = - 393,5 kJ
a)Giải thích tại sao trạng thái chuẩn của C lại là C(g) mà không phải là C (d).
b)Tính ΔH0298 của phản ứng sau:
C(d,s) + O2 (k) ⭢ CO2 (k) (3)
ΔH0298 của phản ứng 3 có phải là ΔH0298, sinh nhiệt của CO2 không ? Tại sao?
Answer:
rrgggf in the world of the world of the world of the up the good morning I will take a user and pass it on the
oxide. b) Silicon dio
43. What is the nature of an enzyme?
a) Vitamin. b) Lipid. c) Carbohydrate. d) Protein
44. Name the enzyme which catalyzes the oxidation-reduction reaction?
a) Transaminase. b) Glutamine synthetase. c) Phosphofructokinase. d) Oxidoreductase
nontido
Answer:
43) protein
44) oxidoreductase
China is the leading producer of
Answer:
Production of some products is highly concentrated in a few countries, China, the leading producer of wheat and ramie in 2013, produces 6% of the world's ramie fiber but only 17% of the world's wheat.
Copper crystallizes in a face-centered cubic unit cell. The density of copper is 8.94 g/cm3. Calculate the length of the edge of the unit cell in pm.
a) 461 pm
b) 361 pm
c) 261 pm
d) 161 pm
e) None of the above
Answer:
361.4 pm is the length of the edge of the unit cell
Explanation:
First, let's calculate the average volume each atom is taking. Start with calculating how many moles of copper we have in a cubic centimeter by looking up the atomic weight. Atomic weight copper = 63.546 Now divide the mass by the atomic weight, getting 8.94 g / 63.546 g/mol = 0.140685488 mol And multiply by Avogadro's number to get the number of atoms: 0.140685488 * 6.022140857x10^23 = 8.472278233x10^22 Now examine the face-centered cubic unit cell to see how many atoms worth of space it consumes. There is 1 atom at each of the 8 corners and each of those atoms is shared between 8 unit cells for for a space consumption of 8/8 = 1 atom. And there are 6 faces, each with an atom in the center, each of which is shared between 2 unit cells for a space consumption of 6/2 = 3 atoms. So each unit cell consumes as much space as 4 atoms. Let's divide the number of atoms in that cubic centimeter by 4 to determine the number of unit cells in that volume. 8.472278233x10^22 / 4 = 2.118069558x10^22 Now calculate the volume each unit cell occupies. 1 cm^3 / 2.118069558x10^22 = 4.721280262x10^-23 cm^3 Let's get the cube root to get the length of an edge. (4.721280262x10^-23 cm^3)^(1/3) = 3.61426x10^-08 cm Now let's convert from cm to pm. 3.61426x10^-08 cm / 100 cm/m * 1x10^12 pm/m = 361.4 pm Doing an independent search for the Crystallographic Features of Copper, I see that the Lattice Parameter for copper at at 293 K is 3.6147 x 10^-10 m which is in very close agreement with the calculated amount above. And since metals expand and contract with heat and cold, I assume the slight difference in values is due to the density figure given being determined at a temperature lower than 293 K.
The sugars can be classified as either aldoses or ketoses.
a. True
b. Fasle
The reaction between NO2 and co to produce no and CO2 is thought to occur in two steps:
Step 1: NO2 + NO2 → + NO + NO3
Step 2: NO3 + CO → NO2 + CO2
The experimental rate law is rate = k[NO2]2.
Required:
a. Write the equation for the overall reaction. do not include phase abbreviations.
b. Identify the intermediate(s).
Answer:
Correct option is
A
Explanation:
The number of molecules of CO involves in the slowest step will be 0 because CO is not involve in the slowest step i.e. rate determing step.
What mass of precipitate (in g) is formed when 250.0 mL of 0.150 M CuCl₂ is mixed with excess KOH in the following chemical reaction?
CuCl₂(aq) + 2 KOH(aq) → Cu(OH)₂(s) + 2 KCl(aq)
Answer:
3.6487g
CuCl2 moles reacted = (0.15×250)/1000
according to balanced chemical equation
precipitated Cu(OH)2 moles = Reacted CuCl2 moles
molar mass of Cu(OH)2 = 63.5+ (17+1)×2 = 97.5
mass of precipitate = (97.5 × 0.15×250)/1000
= 3.648g
What is the mass percentage of C in CH₃CH₂OH? Provide an answer to two decimal places.
Answer:
here's your answer
Explanation:
Molar mass of CH3CH2OH = 46.06844 g/mol
This compound is also known as Ethanol.
Convert grams CH3CH2OH to moles or moles CH3CH2OH to grams
Molecular weight calculation:
12.0107 + 1.00794*3 + 12.0107 + 1.00794*2 + 15.9994 + 1.00794
Percent composition by element
Hydrogen H 1.00794 6 13.128%
Carbon C 12.0107 2 52.143%
Oxygen O 15.9994 1 34.730%
The mass percentage of C in CH₃CH₂OH is 52.14% (to two decimal places)
To calculate the mass percentage of C (Carbon) in CH₃CH₂OH (Ethanol),
First, we will determine the mass of CH₃CH₂OH
Molar mass of CH₃CH₂OH = 46.07 g/mol
Mass of C = 12.01 g/mol
Now, for the mass percentage of C in CH₃CH₂OH,
We will determine the ratio of the total mass of C to the mass of CH₃CH₂OH, and then multiply by 100%
Since we have 2C in CH₃CH₂OH
Then, total mass of C in CH₃CH₂OH = 2 × 12.01 g/mol = 24.02 g/mol
That is,
Mass percentage of C in CH₃CH₂OH = [tex]\frac{24.02}{46.07} \times 100\%[/tex]
Mass percentage of C in CH₃CH₂OH = 0.5213805 ×100%
Mass percentage of C in CH₃CH₂OH = 52.13805%
Mass percentage of C in CH₃CH₂OH ≅ 52.14%
Hence, the mass percentage of C in CH₃CH₂OH is 52.14% (to two decimal places)
Learn more here: https://brainly.com/question/24712044
1)Consider the reactions observed when NaOH(aq) and NH3(aq) were added to the solutions containing Zn2 (aq): a)What is the identity of the precipitate formed when the NaOH(aq) and NH3(aq) were added dropwise (limited amounts added)
Answer:
A white gelatinous precipitate is observed in each case.
Explanation:
Qualitative analysis in chemistry is mostly used to identify the ions present in a sample by adding certain reagents. The observation after adding the reagent often leads to an inference.
When NaOH is added to a solution containing Zn^2+ in drops, a white gelatinous precipitate is observed.
When NH3(aq) is added in drops to a solution containing Zn^2+, a white gelatinous precipitate is also observed.
Copper wire has a high electrical conductivity.
True
False
Answer:
True
Explanation:
Copper has the highest electrical conductivity rating of all non-precious metals: the electrical resistivity of copper = 16.78 nΩ•m at 20 °C. Specially-pure Oxygen-Free Electronic (OFE) copper is about 1% more conductive (i.e., achieves a minimum of 101% IACS).
True is the correct answer.
Compare and contrast the quantum mechanical model and Niels Bohr of the atom
Answer:
the quantum mechanical model VS. Neils Bohr of the atom
Explanation:
The Bohr model and quantum model are models that explain the structure of an atom. ... The key difference between Bohr and quantum model is that Bohr model states that electrons behave as particles whereas quantum model explains that the electron has both particle and wave behavior.
Notice
10 January 2018
Gift A Tree
This is to inform students of Class XII to assemble in the ground on Saturday, 31 January
2018 at 8:00 in the morning to participate in a Tree Plantation Ceremony being organised
by the Environment Club as a part of the Farewell Programme.
Amita/Amit
Secretary, Environment Club)
Exercises
As the Head Boy/ Head Girl, Central Public School, draft a notice informing all students about
a wrist watch that was found near the school canteen.answar
Answer:
gahwidsuacsgsuacayau1joagavahiq8wtw8quavakiafabajozyavqhaigavayquata
Explanation:
vahaiqgahiavavqugafayqigqvsbjsiagwyeiwvvs
Select all that are True.
a. For an isoelectronic series, the species with the most negative charge has the smallest first ionization energy.
b. The removal of an electron from a neutral atom results in a release of energy in the form of heat.
c. For an isoelectronic series, the species with the most positive charge has the smallest first ionization energy.
Consider an equilibrium (K1) that is established after 10 mL of compound A and 10 mL of compound B are mixed. Now, imagine the equilibrium (K2) where 1 mL of compound A is added to 100 mL of compound B. How are K1 and K2 related algebraically (read this question VERY carefully, at least one more time)
The equilibrium constant K₁ = Equilbrium constant K₂.
The equilibrium constant, K, of a reaction, is defined as:
"The ratio between concentration of products powered to their reaction quotient and concentration of reactants powered to thier reaction quotient".
For the reaction:
aA + bB ⇄ cC + dD
The equilibrium constant, K, is:
[tex]K = \frac{[C]^c[D]^d}{[A]^a[B]^b}[/tex]
Now, assuming the reaction of the problem is 1:1:
A + B ⇄ C + D
[tex]K = \frac{[C][D]}{[A][B]}[/tex]
The concentrations of the reactants are directly proportional to the volume added. Thus, we can assume that concentration = Volume. Replacing for K₁ and K₂:
[tex]K_1 = \frac{[C][D]}{[10mL][10mL]} = K_1 = \frac{[C][D]}{100mL^2}[/tex]
In the same way:
[tex]K_2 = \frac{[C][D]}{[1mL][100mL]} = K_2 = \frac{[C][D]}{100mL^2}[/tex]
Thus, we can say:
K₁ = K₂Learn more about chemical equilibrium in:
https://brainly.com/question/4289021?referrer=searchResults
g When 2.50 g of methane (CH4) burns in oxygen, 125 kJ of heat is produced. What is the enthalpy of combustion (in kJ) per mole of methane under these conditions
Answer:
-800 kJ/mol
Explanation:
To solve the problem, we have to express the enthalpy of combustion (ΔHc) in kJ per mole (kJ/mol).
First, we have to calculate the moles of methane (CH₄) there are in 2.50 g of substance. For this, we divide the mass into the molecular weight Mw) of CH₄:
Mw(CH₄) = 12 g/mol C + (1 g/mol H x 4) = 16 g/mol
moles CH₄ = mass CH₄/Mw(CH₄)= 2.50 g/(16 g/mol) = 0.15625 mol CH₄
Now, we divide the heat released into the moles of CH₄ to obtain the enthalpy per mole of CH₄:
ΔHc = heat/mol CH₄ = 125 kJ/(0.15625 mol) = 800 kJ/mol
Therefore, the enthalpy of combustion of methane is -800 kJ/mol (the minus sign indicated that the heat is released).
