1answer.
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
exis [7]
3 years ago
15

20. When the hydrogen supply in the core begins to run out, and the star is no longer generating heat by nuclear fusion, the cor

e becomes unstable and contracts. The outer shellof the star, which is still mostly hydrogen, starts to expand. At this phase the star is called a _____.
a.White dwarf
b.Red dwarf
c.Red Giant
d.Black hole
Chemistry
1 answer:
Triss [41]3 years ago
5 0

Answer:

b

Explanation:

i seached it up

You might be interested in
How many moles are there in 3.9 grams of potassium
polet [3.4K]

Answer:0.025576559594663 mole.

Explanation:

3 0
3 years ago
Which substance has the highest melting point?
Andre45 [30]
<span>A.H2O = water, so it is a liquid at room temperatures (melting point = 0C) and melting point must be below 20C

B.HCl = A gas at room temperatures, so melting point (-114C) is definitely lower than 20C.
Melting points of the aqueous solution (solution in water) at different concentrations are all below that of water, i.e. 0C.

C.CH4 = A gas at room temperatures, so melting point (-182C) must be below 20C.

D.MgCl2 = A white powdery solid at room temperatures, so its melting point (714C) must be above 20C (So this is the only one among the four choices that melts above 20 &deg; C).</span>
7 0
3 years ago
What is the equation used to calculate average velocity
Nadya [2.5K]
Average velocity is the change in distance divided by the time it takes to travel that distance. so the first one.
6 0
3 years ago
A chemist prepares a solution of iron(II) bromide (FeBr2) by measuring out 46. g of iron(II) bromide into a 400. mL volumetric f
schepotkina [342]

Solution

Given mass of FeBr2 = 85.5 g

Molar mass of FeBr2 = 215.65

No. of Moles of FeBr2 = Given Mass / Molar mass = 85.5 / 215.65

No. of Moles = 0.3964

Given Volume is 450 mL i.e. 0.450 L

Now Concentration = 0.3964/0.450

Hence Concentration = 0.881 mol/L

4 0
3 years ago
Can a combination reaction be a redox reaction ?
saul85 [17]

Answer:

Yes A redox reaction can be a combination reaction.

Two elements are mixed in a combination reaction to produce a single product.

Explanation:

Example: water formula

2H2 + O2 → 2H2O

Oxygen is reduced in this reaction when electrons are transferred from hydrogen to oxygen and hydrogen is also oxidized since oxygen from hydrogen accepts electrons. Oxygen is the oxidizing agent and hydrogen is the reducing agent.

2H2 + O2 → 2H2O

4 0
3 years ago
Other questions:
  • How many mg of O2 will react with the TNT?
    6·1 answer
  • This Venn diagram is being used to compare the classification systems of Aristotle and Whittaker.
    10·2 answers
  • In the reaction AI+3O2-&gt;2AI2O3 what coefficient should be placed in front of the AI to balance the reaction 1,2,3,4
    7·1 answer
  • What is the %v/v of a solution made from 136.1 g of ethylene glycol (density is 1.11 g/mL) in water (density 1.00 g/mL) to form
    11·1 answer
  • How do the forces affect men
    7·1 answer
  • Is neon magnetic ? Also what id its freezing point?
    6·2 answers
  • A sample of seawater consists of water, sodium ions, chloride ions, and several other dissolved salts. These ions and salts are
    7·1 answer
  • 1- Calcium Hydroxide + Calcium Bicarbonate
    6·1 answer
  • If the image shows a model of ocean fossils but the actual fossils were found in the desert, what might one assume about the his
    6·1 answer
  • Which of the following represents an element?
    12·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!