19
Gold reacts with the elements in Group 7 of the periodic table.
0.175 g of gold reacts with chlorine.
The equation for the reaction is:
2 Au + 3 Cl2 - 2 AuCla
Calculate the mass of chlorine needed to react with 0.175 g of gold.
Give your answer in mg
Relative atomic masses (Ar): Cl = 35.5 Au = 197

Answers

Answer 1

Answer: The mass of chlorine gas required is 94.6 mg

Explanation:

The number of moles is defined as the ratio of the mass of a substance to its molar mass.

The equation used is:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex] ......(1)

Given mass of gold = 0.175 g

Molar mass of gold = 197 g/mol

Plugging values in equation 1:

[tex]\text{Moles of gold}=\frac{0.175g}{197g/mol}=0.000888 mol[/tex]

The given chemical equation follows:

[tex]2Au+3Cl_2\rightarrow 2AuCl_3[/tex]

By the stoichiometry of the reaction:

If 2 moles of gold reacts with 3 moles of chlorine gas

So, 0.000888 moles of gold will react with = of chlorine gas

Molar mass of chlorine gas = 71 g/mol

Plugging values in equation 1:

[tex]\text{Mass of chlorine gas}=(0.001332mol\times 71g/mol)=0.0946g=94.6mg[/tex]       (Conversion factor: 1 g = 1000 mg)

Hence, the mass of chlorine gas required is 94.6 mg


Related Questions

Diseña un procedimiento que te ayudaría a obtener agua en el desierto usando como fundamento la destilación?

Answers

Answer:b

Explanation:

I searched it

What is the balanced chemical reaction when Aluminium reacts with NaOH to produce NaAlO2 and H2 gas?​

Answers

Answer:

2NaOH + 2Al +2H2O = 2NaAlO2 +3H

Explanation:

Aluminum is an amphoteric element it reacts with both bases and acids to form a salt and hydrogen gas.The reaction is highly exothermic.

Define the boiling and evaporation using kinetic theory

Answers

Answer:

Explanation:

By the kinetic molecular theory (particle model), all matter consists of particles, there are spaces between the particles, the particles are in constant random motion, and there are forces of attraction and repulsion between the particles.

Furthermore, temperature is defined to be a measure of the average kinetic energy of the particles.

Evaporation is a change of phase from liquid to gas explained as follows :

When particles in the liquid phase are heated, they gain kinetic energy and move faster and further apart. Eventually they have enough energy to escape the forces of attraction holding them together in the liquid phase and they move very fast and far from each other and exist in the gaseous phase.

0.18 g of a divalent metal was completely dissolved in 250 cc of acidsolution containing 4.9 g H2SO4 per liter. 50 cc of theresidual acid solution required 20 cc of N/10 alkali forcomplete neutralization. Calculate the atomic weight of metal.​

Answers

goodnight Gucci chunk cubic DDF if f Ch BK

Applicable in case of strong acid–

(i) gets completely ionized in aqueous solutions
(ii) gives H+ ion in aqueous solution
(iii) sour in taste

Which one is correct?

A
i, ii, iii

B
i, ii

C
ii, iii

D
i, iii

Answers

Answer:

A. i, ii, iii

Explanation:

A strong acid gets completely ionized in aqueous solutions releasing a large number of hydrogen ions. It also has a sour taste.

PLEASE HELP ME!

-The compound dissolves in water to form a solution with pH > 7.
- The compound has a low boiling point.

The elements P, Q, R and S have proton number of 1, 7, 11 and 17.
Which of the following pair of elements will react to form a compound with the characteristics stated in the table above?
A. P and Q
B. R and S
C. Q and R
D. P and S​

Answers

Answer:

C

Explanation:

Q and R forms a nitrate. When dissolved in water it will form a solution with a pH greater than 7 because the solution is alkaline.

How do the Carnivorous plants survive without soil?

Answers

Answer:

Carnivorous plants are easy to grow, if you follow a few, simple rules.

Wet all of the time.
Mineral-free water.
Mineral-free soil.
Lots of light.


Wet all of the time.
Carnivorous plants are native to bogs and similar nutrient-poor habitats. As a consequence, the plants live in conditions that are constantly damp. To grow healthy carnivorous plants, it is important to duplicate their habitat as closely as possible. Keep the soil wet or at least damp all of the time. The easiest way to do this is use the tray method. Set the pots in a tray or saucer, and keep water in it at all times. Pitcher plants can grow in soggy soil with the water level in the saucer as deep as 1/2 the pot, but most carnivorous plants prefer damp to wet soil, so keep the water at about 1/4 inch and refill as soon as it is nearly gone. Water from below, by adding water to the tray, rather than watering the plant. This will avoid washing away the sticky muscilage of the sundews and butterworts and keep from closing the flytraps with a false alarm.


Mineral-free water.
Always use mineral-free water with your carnivorous plants, such as rainwater or distilled water. Try keeping a bucket near the downspout to collect rainwater. Distilled water can be purchased at the grocery store, but avoid bottled drinking water. There are simply too many minerals in it. The condensation line from an air conditioner or heat pump is another source of mineral-free water. Reverse-osmosis water is fine to use. Carnivorous plants grow in nutrient poor soils. The minerals from tap water can “over-fertilize” and “burn out” the plants. In a pinch, tap water will work for a short while, but flush out the minerals with generous portions of rainwater, when it is available.


Mineral-free soil.
The nutrient poor soils to which the carnivorous plants have adapted are often rich in peat and sand. This can be duplicated with a soil mixture of sphagnum peat moss and horticultural sand. Be sure to check the peat label for sphagnum moss. Other types will not work well. The sand should be clean and washed. Play box sand is great, and so is horticultural sand. Avoid “contractor’s sand” which will contain fine dust, silt, clay and other minerals. Never use beach sand or limestone based sand. The salt content will harm the plants. The ratio of the mix is not critical, 1 part peat with 1 part sand works well for most carnivorous plants. Flytraps prefer a bit more sand, and nepenthes prefer much more peat. Use plastic pots, as terra cotta pots will leach out minerals over time and stress your plants.

Explanation:


Kayo na Po bahala magpaigsi

Answer:

A simple answer: Carnivores don't eat plants only flesh. So they would not need soil. But it would be hard for Carnivores to get energy because they get energy indirectly from the animals (herbivores) that they eat. How do they get the energy from a herbivore you might ask. Herbivores eat only plants and that gives the herbivore the plant's energy; but if the herbivore gets eaten, it is indirectly transferred into the Carnivore. Hope this helped!!

Carnivore = only feeds on flesh

Herbivore = eats only plants

Omnivore = eats plants and animals/flesh

Hellppppp ASAP Will mark brainliest !!!!Which of the following metals is paramagnetic
A.Beryllium
B.Calcium
C.sodium
D.Magnesium

Answers

Answer:

A. Berryllium is a paramagnetic

gallium sulfide reacts with mercury(I) chloride

Answers

Answerquit

Explanation:snns

ffg full form
gti
ccc

Answers

Answer:

Grand Tourer  Injection

Is the following nuclear equation balanced?

No
Yes

Answers

Answer:

Yes.

The nuclear equation {226/88 Ra → 222/26 Rn + 4/2 He} is balanced. As we know that an alpha particle is identical to a helium atom. This implies that if an alpha particle is eliminated from an atom's nucleus, an atomic number of 2 and a mass number of 4 is lost.

Therefore, the equation will be reduced to:

226 - 4 = 222

88 - 2 = 86

Hence, the equation is balanced.

Explanation:

Answer:

yes

Explanation:

s]imple yes

Someone help me with this science question pls

Answers

Answer: Can i see the question

Explanation:

Arrange the compounds in order of increasing entropy (S).

CH3OH(s)

CH3OH(l),

CH3OH(g),

CH3CH2OH(g)



CH3OH(s) > CH3OH (l) > CH3OH(g) > CH3CH2OH(g)


CH3OH(s) < CH3OH (l) < CH3OH(g) < CH3CH2OH(g)

Answers

Answer: The given compounds are arranged in order of increasing entropy (S) as [tex]CH_{3}OH(s) < CH_{3}OH(l) < CH_{3}CH_{2}OH < CH_{3}OH(g)[/tex]

Explanation:

The degree of randomness present in a substance is called entropy.

This means that more is the number of molecules weakly held together and rapidly moving from one place to another more will be its entropy.

In solids, the molecules are held together strongly with each other. So, they will have least entropy.

In liquids, the molecules are a little loosely held together. So, they have more entropy than a solid substance.

In gases, the molecules are held by weak forces due to which they move rapidly from one place to another. Hence, gases have high entropy as compared to solids and liquids.

Also, more is the molecular mass of a gas less will be its rate of effusion. Hence, less will be its entropy.

[tex]Rate of effusion \propto \frac{1}{\sqrt{M}}[/tex]

where,

M = molecular mass

Thus, we can conclude that given compounds are arranged in order of increasing entropy (S) as [tex]CH_{3}OH(s) < CH_{3}OH(l) < CH_{3}CH_{2}OH < CH_{3}OH(g)[/tex]

Calculate the percent water in ZnSO4.7 H20. Show your work.

Answers

Answer:

43.8%

Explanation:

Find the sum of the relative atomic mass of all the elements constituting the compound, which is known as the relative formula mass;

[tex]M_{r} = Relative \ formula \ mass \\\\M_{r} \ of \ ZnSO_{4} = 65.4 + 32.1 + 4(16) \\\\M_{r} \ of \ ZnSO_{4} = 97.5 + 64 \\\\M_{r} \ of \ ZnSO_{4} = 161.5 \\\\M_{r} \ of \ H_{2}O = 18 \\\\M_{r} \ of \ ZnSO_{4}.7H_{2}O = 161.5 + 7(18) \\\\M_{r} \ of \ ZnSO_{4}.7H_{2}O = 287.5[/tex]

Then, divide the relative formula mass of all the water by that of the whole compound

w = % water

[tex]w = \frac{7(18)}{287.5} * 100 \\\\w = 0.43826... * 100\\\\w = 43.826...[/tex]

w = 43.8%

what is the oxidation state of p in po4 3

Answers

Answer:+5

Explanation: A P3X



Are your knees the elbows of your legs or are your elbows the knees of your

arms?

A.knees are elbows of your legs

B.elbows are knees of your arms

C.both

Answers

Answer:

Both :)

Explanation:

Knees and elbows are the types of joints that are present to move the parts of the body attached to it. The knees are the elbows, and the elbows are the knees.

What are joints?

The joints knees and elbows work like the door and allow the movement of the attached body parts in back and forth directions.

The elbow of the arm region and the knee of the leg region have similar functions and are homologous in the function that moves the leg of the lower region and the arm of the upper region.

Therefore, option c. both is the correct option.

Learn more about knee and elbow here:

https://brainly.com/question/27056104

what's is area of square that has a side of 3.4cm​

Answers

Answer:

11.56

Explanation:

Answer:
11.56cm^2

Explanation:
3.4 x 3.4 = 11.56

should i microwave a browney

Answers

Answer:

Ha why not but if it is not cooked.

yes and yes and yes and absolutely yes. Yes do it

URGENT!!!

Which of the following describes a property of water that helps sustain marine life forms? (5 points)
a. Open spaces in water's solid structure makes its solid state less dense than its liquid state.
b. Water contracts on cooling below 4 °C, lowering its density until it reaches 0 °C.
c. Water freezes from bottom to top, which allows it to form a solid layer of ice only at the bottom of rivers and lakes.
d. Water has a very low specific heat capacity, allowing it to heat up quickly.

Answers

Answer:

a.) open spaces in waters solid structure makes its solid state less dense than its liquid state.

Answer: It is a.) open spaces in waters solid structure makes its solid state less dense than its liquid state.

Explanation: This is because the solid state of water is less dense than its liquid state due to free spaces in its solid structure.

PLEASE HELP ME!

Aspartame is an artificial sweetener that is 160 times sweeter than table sugar. It is marketed as Pal-Sweet. The molecular formula of aspartame is C¹⁴H18N²O5.

i) Name the elements that made up aspartame. [2 marks]

(ii) Calculate the relative molecular mass of aspartame. [2 marks]

(iii) Calculate the number of moles in 7.35g aspartame. [3 marks]

(iv) Calculate the number of molecules in 5.88 g aspartame. [2 marks]

(v) Calculate the mass in grams of one molecule of aspartame. (H=1, C=12, N=14, 0=16, N = 6 x 10²³mole) [3 marks] ​

Answers

Answer:

A. Carbon, Hydrogen, Nitrogen, and Oxygen

B. 12(14) + 1(18) +12(2)+16(5)= 294.20g

C. 7.35/294.3=0.0250mol

D. 5.88g/294.3=0.01997961264 × 6.02 × 10^2= 12.028

Explanation:

HELP NEEDED!!!
80.0 mL of Ba(OH)2(aq) solution is used to completely titrate 60.0 mL of 0.150 mol/L HCl(aq) solution. What is the concentration of the barium hydroxide solution in mol/L.

Answers

Answer:

0.1125  mol/L

Explanation:

application fomula:

C1V1=C2V2

C1 is concentration of Ba(OH)2

V1 is volume of Ba(OH)2

C2 is concentration of HCl

V2 is volume of HCl

Which of the following compounds is usually
added to a swimming pool to prevent the growth
of algae ?
A. Caso
B. Cuso
C. PbSO
D. MgSO
4
4
4
4​

Answers

The answer is C which is PbSo

Which of the following explains the VSEPR geometry of a water molecule?



O It is tetrahedral because there are four bonded pairs around oxygen.
O It is bent because there are four bonded pairs around oxygen.
O It is tetrahedral because there are two bonded pairs and two lone pairs around oxygen.
O It is bent because there are two bonded pairs and two lone pairs around oxygen.

Answers

It is bent because there are two bonded pairs and two lone pairs around oxygen.

According to VSEPR theory, geometry of water molecule is bent.

Water is a simple molecule consisting of one oxygen atom bonded to two different hydrogen atoms. The molecule adopts a bent structure because of the two lone pairs of electrons on the oxygen atom.The total number of electron pairs in the valence shell of the oxygen atom is 2.The resulting molecular shape is bent with an H-O-H angle of 104.5°.

Learn more:

brainly.com/question/12775505

Answer:

It is tetrahedral because there are two bonded pairs and two lone pairs around oxygen.

Explanation:

Took it

(1) The solubility of Salt AB2(s) is 5mol/dm^3. (a) Obtain an expression for the solubility product of Salt AB2,in terms of s.

Answers

Answer:

See explanation

Explanation:

Let the equation of dissolution be;

AB2(s) ⇄A(aq) + 2S

Hence;

Ksp = [A] [2s]^2

Let the concentration of the species be s

Ksp= s × (2s)^2

Ksp= 4s^3

Since s= 5mol/dm^3

Ksp = 4(5mol/dm^3)^3

Ksp = 500 mol^2dm^-6

Cho m gam FeO tác dụng hết với dung dịch H2SO4, thu được 200 ml dung dịch FeSO4 1M. Giá trị của m là

Answers

Answer: The mass of [tex]FeO[/tex] required is 14.37 g

Explanation:

Molarity is calculated by using the equation:

[tex]\text{Molarity}=\frac{\text{Moles}}{\text{Volume}}[/tex] ......(1)

We are given:  

Molarity of iron (II) sulfate = 1 M

Volume of solution = 200 mL = 0.200 L (Conversion factor: 1 L = 1000 mL)

Putting values in equation 1, we get:

[tex]\text{Moles of }FeSO_4=(1mol/L\times 0.200L)=0.200mol[/tex]

The chemical equation for the reaction of FeO with sulfuric acid follows:

[tex]FeO+H_2SO_4\rightarrow FeSO_4+H_2O[/tex]

By stoichiometry of the reaction:

If 1 mole of iron (II) sulfate is produced by 1 mole of FeO

So, 0.200 moles of iron (II) sulfate will produce = [tex]\frac{1}{1}\times 0.200=0.200mol[/tex] of FeO

The number of moles is defined as the ratio of the mass of a substance to its molar mass. The equation used is:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex]

We know, molar mass of [tex]FeO[/tex] = 71.84 g/mol

Putting values in above equation, we get:

[tex]\text{Mass of }FeO=(0.200mol\times 71.84g/mol)=14.37g[/tex]

Hence, the mass of [tex]FeO[/tex] required is 14.37 g

Heavy rains fill a reservoir, causing the dam that holds the water to break. As a result, the areas downstream are suddenly flooded. Which question would a scientist seek to answer?

Answers

Answer:

"How to prevent the collapse of the dam that contains water from heavy rains?"

Explanation:

Scientists must work to create innovations capable of bringing benefits to human life and combating disadvantageous and harmful situations. The overflow of dams is something very harmful, as the resulting flooding can cause structural, economic and even public health problems. When this overflow is caused by natural elements, such as heavy rains, the work of scientists in solving these issues is even more important and necessary. In order to resolve the dam failure caused by excess rainwater, scientists must work to answer the following question:

"How to prevent the collapse of the dam that contains water from heavy rains?"

Equation balancing
a. S(s) + O2(g) → SO3(g)
b. 2Al(s) + 3Cl2(g) ► 2AICI3(s)
E. 2NaOH(s) + H2SO4(ac) —Na2So (ac) + H2O(l)
d. C3H8(g) + 50(g) -3C02(g) + 4H2O(g)

Answers

Answer:

For a: The balanced equation is [tex]2S(s)+3O_2(g)\rightarrow 2SO_3(g)[/tex]

For c: The balanced equation is [tex]2NaOH(s)+H_2SO_4(aq)\rightarrow Na_2SO_4(aq)+2H_2O(l)[/tex]

Explanation:

A balanced chemical equation is one where all the individual atoms are equal on both sides of the reaction. It follows the law of conservation of mass.

For (a):

The given unbalanced equation follows:

[tex]S(s)+O_2(g)\rightarrow SO_3(g)[/tex]

To balance the equation, we must balance the atoms by adding 2 infront of both [tex]S(s)[/tex] and [tex]SO_3[/tex] and 3 in front of [tex]O_2[/tex]

For the balanced chemical equation:

[tex]2S(s)+3O_2(g)\rightarrow 2SO_3(g)[/tex]

For (b):

The given balanced equation follows:

[tex]2Al(s)+3Cl_2(g)\rightarrow 2AlCl_3(s)[/tex]

The given equation is already balanced.

For (c):

The given unbalanced equation follows:

[tex]2NaOH(s)+H_2SO_4(aq)\rightarrow Na_2SO_4(aq)+H_2O(l)[/tex]

To balance the equation, we must balance the atoms by adding 2 infront of [tex]H_2O(l)[/tex]

For the balanced chemical equation:

[tex]2NaOH(s)+H_2SO_4(aq)\rightarrow Na_2SO_4(aq)+2H_2O(l)[/tex]

For (d):

The given balanced equation follows:

[tex]C_3H_8(g)+5O_2(g)\rightarrow 3CO_2(g)+4H_2O(g)[/tex]

The given equation is already balanced.


Bacteria, viruses, parasites, and mold are examples of which category of hazard-causing agents?

Answers

Answer:

abiotic infectious agent

Explanation:

not sure tho

Biological hazards include microorganisms such as bacteria, viruses, yeasts, molds and parasites. Some of these are pathogens or may produce toxins. A pathogenic microorganism causes disease and can vary in the degree of severity. Examples of biological hazards include Salmonella, E.

Source: https://www.canr.msu.edu/news/biological_chemical_and_physical_hazards_assessed_with_haccp

ion has a mass number of 65, 36 neutrons, and a charge of +1
. Identify the element symbol, and determine the number of protons and electrons in this ion.

Answers

Answer:

Copper; Symbol is Cu

Protons = 29

Electrons = 29

Mass number = Protons + Neutrons

•°• Protons = Mass number - Neutrons

= (65-36)

= 29

Electrons is equal to the number of protons in a nucleus.

Hello Everyone ✌
hw r y'all doin
Pls answer the below questions

What is Malleability
What is ductility
What is Sonorous

Answers

Answer:

Malleability describes the property of a metal's ability to be distorted below compression. It is a physical property of metals by which they can be hammered, shaped and rolled into a very thin sheet without rupturing. A malleable fabric could be planate by blow or rolling.

Explanation:

Ductility is the property of a solid, like a metal, to deform under a tensile stress (force). So if you pull on two ends of a metal wire or bar, and it “stretches” you have a ductile substance. Though I must caution that you don't confuse the definition of ductile to mean elastic. They are not synonyms. It is the opposite of brittle. When a ductile item breaks, it is after necking, where the diameter of the wire in question reduces as the length elongated. A brittle, or non-ductile material simple tears apart in a sharp and quick fashion with little to no visible necking taking place.

sonorous: producing sound (as when struck)

Malleability describes how mallaebale the metal is
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