Answer:
1. Main sequence stars have different masses. The common characteristic they have is their source of energy. They burn fuel in their core through the process of fusing hydrogen atoms into helium.
2. Supergiants are among the most massive and most luminous stars. Supergiant stars occupy the top region of the Hertzsprung–Russell diagram with absolute visual magnitudes between about −3 and −8. The temperature range of supergiant stars spans from about 3,400 K to over 20,000 K.
3. Supergiants develop when massive main-sequence stars run out of hydrogen in their cores.
4. a supernova occur When the pressure drops low enough in a massive star, gravity suddenly takes over and the star collapses in just seconds. This collapse produces the explosion.
5. when a star has reached the end of its life and explodes in a brilliant burst of light
Explanation:
H2O means water, which is made of two hydrogen and one oxygen atoms.
Oxygen is a gas that your body needs to function. Oxygen comes from the air.
The answer to this problem is Beryllium is an alkaline earth metal.
Answer:
a. Moles of 
= 0.001643 moles
b. 0.296 g
c. 0.3098 g
d. Not acceptable
Explanation:
a.
Considering:
Or,
Given :
For :
Molarity = 0.1052 M
Volume = 15.62 mL
The conversion of mL to L is shown below:
1 mL = 10⁻³ L
Thus, volume = 15.62×10⁻³ L
Thus, moles of :
Moles of = 0.001643 moles
b.
The reaction of NaOH with the acetylsalicylic acid is in the ratio of 1:1.
Thus, Moles of NaOH = Moles of acetylsalicylic acid = 0.001643 moles
Molar mass of acetylsalicylic acid = 180.16 g/mol
The formula for the calculation of moles is shown below:
Thus,
Mass = Moles * Molar mass = 0.001643 moles * 180.16 g/mol = 0.296 g
c.
1.159 g of sample contains 0.296 g of acetylsalicylic acid
1.213 g of sample contains 
g of acetylsalicylic acid
Mass of acetylsalicylic acid = 0.3098 g = 309.8 mg
d. Sample contains = 309.8 mg
Manufacturer claiming = 315 mg to 335 mg
Thus , it is not acceptable.
Answer:
Explanation:
True or false 4 questions help please!
Most mixtures are not physical changes.
True
False FALSE when I add solid NaCl salt to water I no longer have a solid salt, I have a solution of sodium and chlorid ions in liquid water. this is physical change
Chemical Changes do not create a new substance.
True
False FALSE 0ne of the proofs that you have a chemical change is the presence of a new substance
Fire is an example of a Chemical Change.
True TRUE fire is oxygen reacting wiIh mattter to form new compounds
False
Explosions are not chemical changes.
It depends on the explosion if I blow up a balloon until it POPS!! that is physical chame. If I light a firecracker and it explodes, that is a chemical change of oxygen reacting with hot gunpowder
A change in color and odor are both examples of chemical changi
I would rewrite the question as
A change in color and odor both INDICATE a chemical change
and that is
True TRUE
False
F
True Fire is an example of a Chemical Change.
True
False
Explosions are not chemical changes.
True
False
