A student determines the calcium content of a solution by first precipitating it as calcium hydroxide, and then decomposing the hydroxide to calcium oxide by heating. How many grams of calcium oxide should the student obtain if his solution contains 55.0 mL of 0.458 M calcium nitrate?

Answer:

C. T>617 K

Explanation:

We are given that

[tex]\Delta H=176KJ/mol[/tex]

[tex]\Delta S=0.285KJ/K\cdot mol[/tex]

We have to find the temperature at which the reaction is spontaneous.

When

[tex]\Delta H>0, \Delta S>0[/tex]

Therefore, the reaction is spontaneous at certain range of temperature.

Option A is not true.

[tex]\Delta G=\Delta H-T\Delta S[/tex]

When [tex]\Delta G[/tex] is negative, then  the reaction is spontaneous.

[tex]\Delta G=176-0.285T[/tex]

When T<50

Suppose T=49 K

[tex]\Delta G=176-49\times 0.285>0[/tex]

Therefore, [tex]\Delta G is positive[/tex].Hence, the  reaction is not spontaneous.

Option B is wrong.

C.T>617K

Suppose T=618 K

[tex]\Delta G=176-0.285\times 618=-0.13<0[/tex]

Therefore, [tex]\Delta G is negative[/tex].Hence, the  reaction is spontaneous.

So, option C is true.

D.T<617 K

Suppose T=616 K

[tex]\Delta G=176-0.285\times 616=0.44>0[/tex]

Therefore, [tex]\Delta G is positive[/tex].Hence, the  reaction is not spontaneous.

So, option D is not true.

Answer:

Average velocity of car = 50 km/h

Explanation:

Given information;

Distance cover by man in his car = 25 kilometer

Time taken by man to cover distance = 30 min

Find:

Average velocity of car

Computation:

Time taken by man to cover distance = 30 min

Time taken by man to cover distance = 30 / 60

Time taken by man to cover distance = 0.5 hour

Average velocity = Distance / Time

Average velocity of car = Distance cover by man in his car / Time taken by man to cover distance

Average velocity of car = 25 / 0.5

Average velocity of car = 50 km/h

Answer:

Option B.

C₆H₁₀O₅ + 6O₂ —> 6CO₂ + 5H₂O

Explanation:

To know which option is correct, we shall write the balanced equation for the combustion of cellulose. This is illustrated below:

C₆H₁₀O₅ + O₂ —> CO₂ + H₂O

There are 6 atoms of C on the left side and 1 atom on the right side. It can be balance by writing 6 before CO₂ as shown below:

C₆H₁₀O₅ + O₂ —> 6CO₂ + H₂O

There are 10 atoms of H on the left side and 2 atoms on the right side. It can be balance by writing 5 before H₂O as shown below:

C₆H₁₀O₅ + O₂ —> 6CO₂ + 5H₂O

There are a total of 7 atoms of O on the left side and a total of 17 atoms on the right side. It can be balance by writing 6 before O₂ as shown below:

C₆H₁₀O₅ + 6O₂ —> 6CO₂ + 5H₂O

Now, the equation is balanced.

Thus, option B gives the correct answer to the question.

m=y2 −y1/x2-x1

Explanation:

3-5/2-12=1/5

Answer:

True

Explanation:

An atom would carry more protons if positively charged, an equal amount of both protons and electrons if neutral, and more electrons if charged negative.

Answer:

4 Fe  +   3 O2    ⇒  2  Fe2O3

Explanation:

iron metal reacts with oxygen gas to produce solid iron (III) oxide.

Fe   +   O2  ⇒  Fe2O3

4 Fe  +   3 O2    ⇒  2  Fe2O3

The balanced chemical equation for the reaction is

4Fe(s) + 3O₂(g) → 2Fe₂O₃(s)

From the question,

We are to write a balanced chemical equation for the reaction of iron metal with oxygen gas to produce solid iron (III) oxide

Iron metal is represented as Fe(s)

Oxygen gas is represented as O₂(g)

and Solid iron (III) oxide is represented as Fe₂O₃(s)

Now, we will write the balanced chemical equation for the reaction

The balanced chemical equation for the reaction is

4Fe(s) + 3O₂(g) → 2Fe₂O₃(s)

This means 4 moles of the iron metal reacts with 3 moles of oxygen gas to produce 2 moles of solid iron (III) oxide.

Hence, The balanced chemical equation for the reaction is

4Fe(s) + 3O₂(g) → 2Fe₂O₃(s)

Learn more here: https://brainly.com/question/23877810

Answer:

D. a positive ion and a negative ion

Explanation:

Ionic bonds is formed from the attraction of opposite full charges. So a positive ion and a negative ion will make a ionic bond (Similar to how Na+ and Cl- ions make salt - which is basically a crystal of ions bonded via ionic bonds)

Answer:

Explanation:

Why is there a star * behind the question.

CaCl2

Al2(SO4)3

NaOH

Answer:

Glycerol;Pyruvate

Explanation:

Metabolism of triglycerides occur through a process known as lipolysis. During triglyceride metabolism, Glycerol is converted to pyruvate or glucose through glycolysis or gluconeogenesis respectively. Glycerol enters these pathways by being converted to glycerol-3-phosphate (reaction catalyzed by glycerol kinase) which can in turn be converted to dihydroxyacetone phosphate (reaction catalyzed by glycerol-3-phosphate dehydrogenase).

NOTE: Dihydroxyacetone phosphate is a compound/substrate found in both glycolysis and gluconeogenesis.

The end product of glycolysis is pyruvate; this pyruvate, under aerobic condition is converted to acetyl coA (reaction catalyzed by pyruvate dehydrogenase complex), an intermediary of the Tricarboxylic acid cycle.

Answer:

3.36×10²⁶ g

Explanation:

Molar mass ( O2) = 32g/mol

mole(O2) = 1.05×10²⁵mol

Mass(O2) = ?

mole(n)= mass(m)/Molar mass(M)

n×M = m

1.05×10²⁵ mol × 32g/mol = mass

mass= 3.36×10²⁶ g

Answer:

overall I think one answer

Answer:

Amount of oxygen needed is 5,000 liter

Explanation:

Given:

Percent of air in oxygen = 1%

Find:

Oxygen if 50 liter of wind

Computation:

Oxygen if 50 liter of wind  = 50 liter wind[100% / 1% ]

Oxygen if 50 liter of wind  = 50 liter wind[100]

Oxygen if 50 liter of wind  = 50[100]

Oxygen if 50 liter of wind  = 5,000

So,

Amount of oxygen needed is 5,000 liter

Answer:

D. 2

Explanation:

On the right side of the equation:

Al has 1, Zn has 3, NO3 has 6

But on the left side:

Al has 1, Zn has 1, NO3 has 3

1. So, if we add a coefficient of 2 to Al(NO3)3, then NO3 now has 6-which is what it needs.

2. But now the Al on the right side of the equation is not balanced, so give it a coefficient of 2.

3. To make the Zn balance, just add a coefficient of 3 on the left side of the equation.

Which leaves us with:

2Al + 3Zn(NO3)2 --> 2Al(NO3)3 + 3Zn

And now there are the same number of each compound on both sides of the equation.

Good luck! If you have any questions on this answer leave a comment :)

Answer:

4.. increases

5..lowers

6.. increases

7.. increases

8.. speed

Answer:

When a substance is heated, its temperature rises because its molecules move faster and gain thermal energy. Temperature measures the "hotness" or "coldness" of an object. The term heat refers to thermal energy being transferred from a hotter system to a cooler one.

Answer:

carbondioxe and zinc as solid

Answer:

B. Anyone can make a claim, but a scientific claim is backed by experimental evidence.

<3 Have a nice day!!

Answer:

the awnser is B i got it right

Explanation:

Answer:

i believe energy is your answer here

Answer:

reaction

Explanation:

A reaction is defined as a process where the chemical transformation takes place from one form to some other form. Here, two different chemical substances are reacted together to form some other completely different product.

A hydrogenation process is a chemical process where between the molecular hydrogen and some another element or a compound. This process is usually carried out in the presence of catalyst mainly nickel, platinum or palladium.

Thus, in hydrogenation of a double bond, the catalyst is used to speed up the reaction. The first step in this process is adsorption process, the second step is the diffusion process, the third step is the reaction process and the last step is the desorption process.

Answer:

2.0 × 10² g

Explanation:

Step 1: Write the balanced equation

2 NO₂ + 0.5 O₂ ⇒ N₂O₅

Step 2: Calculate the theoretical yield, in moles, of N₂O₅

The molar ratio of NO₂ to N₂O₅ is 2:1.

6.0 mol NO₂ × 1 mol N₂O₅/2 mol NO₂ = 3.0 mol N₂O₅

Step 3: Calculate the theoretical yield, in grams, of N₂O₅

The molar mass of N₂O₅ is 108.01 g/mol.

3.0 mol × 108.01 g/mol = 3.2 × 10² g

Step 4: Calculate the real yield, in grams, of N₂O₅

real yield = theoretical yield × percent yield

real yield = 3.2 × 10² g × 61.1% = 2.0 × 10² g

Answer:

hanigin ng mga pule natin

Answer:

See explanation

Explanation:

A system is said to have attained dynamic equilibrium when the rate of forward reaction and the rate of reverse reaction are equal.

Considering the system under consideration;

I2(s)⇄I2(g)

Heating the container converts solid iodine to purple coloured iodine vapour.

At equilibrium, there will be no net change in the amount of solid iodine and iodine vapour present in the system because the two processes (forward and reverse reactions) occur at the same rate at equilibrium.

Answer:

About 96 to 256 ATP molecules are produced.

Explanation:

About 96 to 256 ATP molecules may be synthesized in the full metabolism in oligosaccharide because one oligosaccharide molecule has 3 to 8 glucose atoms. About 30 to 32 ATP are produced from one glucose molecule so from three glucose molecule, 96 ATP produced whereas 256 ATP molecules are produced from 8 glucose molecules so we can say that About 96 to 256 ATP molecules from one oligosaccharide.

Answer: so in this question are reactants are calcium hydroxide and ammonium chloride

Explanation: first of all know that a salt would be formed so here the salts present are calcium and chloride so they would react to form the salt calcium chloride, then since ammonium ions are present ammonia gas would be formed then, hydroxide ions (OH) are also present so water would be formed so our final products would be calcium chloride , ammonia and water .

WORD EQUATION

calcium hydroxide+ ammonium chloride⇒ calcium chloride+ ammonia+ water

CHEMICAL EQUATION

CA(OH)2+2NH4CL⇒ CACL2+2NH3+2H2O

Answer: The statement diffusion occurs when particles spread from areas where they are less concentrated to areas where they are more concentrated, is false.

Explanation:

When particles or atoms of a substance are able to move rapidly from one place to another then it is called diffusion.

During diffusion, particles tend to move apart from each other.

For example, spreading of dye molecules into water.

Thus, we can conclude that the statement diffusion occurs when particles spread from areas where they are less concentrated to areas where they are more concentrated, is false.

Answer:

D. 450 J/kgK

Explanation:

Using the formula as follows:

Q = m × c × ∆T

Where:

Q = amount of heat absorbed/released (J)

m = mass of substance (g)

c = specific heat capacity

∆T = change in temperature (°C)

According to the information provided in this question:

Q = 267.3 kJ = 267300J

m = 18kg

∆T = 318K - 285K = 33K

c = ?

Q = m × c × ∆T

c = Q ÷ m∆T

c = 267300 ÷ 18 × 33

c = 267300 ÷ 594

c = 450 J/kgK

Answer: The report prepared is a nontestimonial hearsay.

Explanation:

The nontestimonial hearsay can be defined as the expert opinion or statement given casually and not for the purpose of keeping or considering it as record by the government agent or agency. Here the given conclusion provided by the chemical expert is an example of nontestimonial hearsay because it is not the output of experimental and analytical procedures instead it is a casual opinion. Testimonial hearsay include the evidences that are based on detailed and thorough analytic procedures.

Answer:

mg2+ because it is a very good idea