answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
erik [133]
2 years ago
8

The Sun is a main sequence star. During the last stage of its life cycle, it will become a white dwarf. It will shrink in size,

but it will be very hot. Which of the stars in your chart do you think is a white dwarf and why?
Chemistry
2 answers:
kramer2 years ago
4 0

Answer:

The ones with an absolute magnitude that is more than 5 and have a surface temperature between 25,000 and 7,500.

Barnard's star and  Proxima Centauri because their absolute magnitude is more than 5 and they have a surface temperature of 25,000 7,500.

Explanation: For edmentum users

dangina [55]2 years ago
3 0
The one that is tiny and white. 
You might be interested in
Given these reactions, where X represents a generic metal or metalloid 1) H2(g)+12O2(g)⟶H2O(g)ΔH1=−241.8 kJ 1) H2(g)+12O2(g)⟶H2O
Bond [772]

Answer:

ΔH = -793,6 kJ

Explanation:

It is possible to obtain ΔH of this reaction using Hess's law that says you can sum the half-reactions ΔH to obtain the ΔH of the global reaction:

If half-reactions are:

1) H₂(g) + ¹/₂O₂(g) ⟶ H₂O(g) ΔH₁ = −241.8 kJ

2) X(s) + 2Cl₂(g) ⟶ XCl₄(s) ΔH₂ = +356.9 kJ  

3) ¹/₂H₂(g) + ¹/₂Cl₂(g) ⟶ HCl(g) ΔH₃ = −92.3 kJ

4) X(s) + O₂(g) ⟶ XO₂(s) ΔH₄ = −639.1 kJ

5) H₂O(g) ⟶ H₂O(l) ΔH₅ = −44.0 kJ

The sum of (4) + 4×(3) - (2) - 2×(1) - 2×(5) is:

(4) X(s) + O₂(g) ⟶ XO₂(s) ΔH = −639.1 kJ

+4×(3) 2H₂(g) + 2Cl₂(g) ⟶ 4HCl(g) ΔH = −369,2 kJ

-(2) XCl₄(s) ⟶ X(s) + 2Cl₂(g) ΔH = -356,9 kJ

-2×(1) 2H₂O(g) ⟶ 2H₂(g) + O₂(g) ΔH = +483,6 kJ

-2×(5) 2H₂O(l) ⟶ 2H₂O(g) ΔH = +88.0 kJ

= <em>XCl₄(s) + 2H₂O(l) ⟶ XO₂(s) + 4HCl(g)</em>

Where ΔH is:

ΔH = -639,1 kJ -369,2 kJ -356,9 kJ +483,6 kJ +88,0 kJ

<em>ΔH = -793,6 kJ</em>

I hope it helps!

5 0
2 years ago
If Maria winks exactly 5 times every minute while she is awake and she sleeps exactly 8 hours a day, how many times does Maria w
irina1246 [14]
24 minus 8 is 16
5 times 60 is 300
300 times 16 is 4800.
She winks 4800 times a day
5 0
2 years ago
The double bond between carbon and oxygen is similar to an alkene C-C, except that C o is: a) shorter and weaker. b) shorter and
mina [271]

Answer:

the double bond between c and o is shorter and weaker

Explanation:

this is because the bond between c and o involves unequal sharing of electrons whole c and c involves hybridization sp2 of orbitals and also catenation phenomenon in which carbon could form long chain with it's other carbon

5 0
2 years ago
Hydrogen sulfide (H2S) is a common and troublesome pollutant in industrial wastewaters. One way to remove H2S is to treat the wa
Kryger [21]

Explanation:

As the given reaction is as follows.

     H_{2}S(aq) + Cl_{2}(aq) \rightarrow S(s) + 2H^{+}(aq) + 2Cl^{-}(aq)

So, according to the balanced equation, it can be seen that rate of formation of Cl^{-} will be twice the rate of disappearance of H_{2}S .

And, it is known that rate of disappearance of reactant will be negative and rate of formation of products will be positive value.

This means that,

Rate of the reaction = -Rate of disappearance of H_{2}S

                 = k[H_{2}S][Cl_{2}]

                 = (3.5 \times 10^{-2}) \times (2 \times 10^{-4}) \times (2.8 x 10^{-2})

                 = 1.96 \times 10^{-7} M/s

Therefore, calculate the rate of formation of Cl^{-} as follows.

Rate of formation of Cl^{-} = 2 \times 1.96 \times 10^{-7}

                                        = 3.92 \times 10^{-7} M/s

Thus, we can conclude that the rate of formation of Cl^{-} is 3.92 \times 10^{-7} M/s.

5 0
2 years ago
A chemical engineer calculated that 15.0 mol H2 was needed to react with excess N2 to prepare 10.0 mol NH3. But the actual yield
rjkz [21]

Answer:

The actual number of moles is 9 moles.

It is less than 15

Number of moles needed is 9 moles

Explanation:

15H2 + 10N2 ——-> 10NH3

Now from the question, we can see that the percentage yield is 60%

The percentage yield can be calculated as actual moles of H2/Theoretical moles of H2 * 100%

From the equation, we can see that the theoretical number of moles of hydrogen is 15.

Now to get the actual : 60 = x/15 * 100

x = 9

The actual number of moles is 9 moles.

It is less than 15

Number of moles needed is 9 moles

8 0
2 years ago
Other questions:
  • Physical properties of glass bottle
    9·1 answer
  • Radioactive isotopes are used as contrast dyes to study soft tissues such as the gastrointestinal tract. The radiocontrast dyes
    7·2 answers
  • A 1.00 l solution contains 3.50×10-4 m cu(no3)2 and 1.75×10-3 m ethylenediamine (en). the kf for cu(en)22+ is 1.00×1020. what is
    6·1 answer
  • How does a conductivity apparatus test whether a solution has ionic or covalent substances in it? It fails to light up except in
    8·2 answers
  • What is the identity of the unknown ink?use evidence to support your claim.
    5·1 answer
  • A certain compound with a molar mass of 120.0 g/mol crystallizes with the sodium chloride (rock salt) structure. The length of a
    10·1 answer
  • Which of the following statements is true concerning the reaction given below?2H2S(g) + O2(g) → 2S(s) + 2H2O(g)a. The reaction i
    11·1 answer
  • Are all the molecules in the picture the same?
    7·2 answers
  • In one compound of lead and sulfur, there are 6.46 g of lead
    13·1 answer
  • Select the term that matches each definition:
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!