All categories

3 years ago

The Sun is a yellow star that's both average in brightness and temperature and is classified as

Chemistry

1 answer:

Roman55 [17]3 years ago

7 0

Answer:

Classifying stars according to their spectrum is a very powerful way to begin to understand how they work. As we said last time, the spectral sequence O, B, A, F, G, K, M is a temperature sequence, with the hottest stars being of type O (surface temperatures 30,000-40,000 K), and the coolest stars being of type M (surface temperatures around 3,000 K). Because hot stars are blue, and cool stars are red, the temperature sequence is also a color sequence. It is sometimes helpful, though, to classify objects according to two different properties. Let's say we try to classify stars according to their apparent brightness, also. We could make a plot with color on one axis, and apparent brightness on the other axis, like this:

Explanation:

You might be interested in

What is the energy in joules of one photon of microwaveradiation with a wavelength 0.122m?

pentagon [3]

Answer: The energy of photon is $162.93\times 10^{-26}J$

Explanation:

The relation between energy and wavelength of light is given by Planck's equation, which is:

$E=\frac{hc}{\lambda}$

where,

E = energy of the light = ?

h = Planck's constant = $6.626\times 10^{-34}Js$

c = speed of light = $3\times 10^8m/s$

$\lambda$ = wavelength of photon = 0.122 m

Putting values in above equation, we get:

$E=\frac{(6.626\times 10^{-34}Js)\times (3\times 10^8m/s)}{0.122m}\\\\E=162.93\times 10^{-26}J$

Hence, the energy of photon is $162.93\times 10^{-26}J$

3 0

3 years ago

What is the enthalpy change (in kj) of a chemical reaction that raises the temperature of 250.0 ml of solution having a density

Pepsi [2]

250 ml * 1.25 g/ml * 3.74 j/g-K * 9.2 K = 10.752 kJ Pretty much, all you need to do here is multiply all of these out to get your final answer. Not all questions are this easy, but this is certainly one of them.

3 0

3 years ago

Read 2 more answers

SnO2 + 2 H2 ——> Sn + 2 H2O

SpyIntel [72]

Answer:

0.15g

Explanation:

Given parameters:

Number of molecules of water = 1.2 x 10²¹ molecules

Unknown:

Mass of SnO₂ = ?

Solution:

To solve this problem, we have to work from the known to the unknown specie;

SnO₂ + 2H₂ → Sn + 2H₂O

Ensure that the equation given is balanced;

Now,

the known species is water;

6.02 x 10²³ molecules of water = 1 mole

1.2 x 10²¹ molecules of water = $\frac{1.2 x 10^{21} }{6.02 x 10^{23} }$ = 0.2 x 10⁻²moles

Number of moles of water = 0.002moles

From the balanced chemical equation:

2 mole of water is produced from 1 mole of SnO₂

0.002 moles of water will be produced from $\frac{0.002}{2}$ = 0.001moles

To find the mass;

Mass = number of moles x molar mass

Molar mass of SnO₂ = 118.7 + 2(16) = 150.7g/mol

Mass = 0.001 x 150.7 = 0.15g

3 0

3 years ago

What would make bromide salt insoluble in water?

anzhelika [568]

Its doesn't dissolve in water!

3 0

3 years ago

explain the law of conservative of energy, give a specific example using kinetic and potential energy that shows how energy is c

KiRa [710]

Answer:

The Law of Conservation of Energy states that energy cannot be created or destroyed. In other words, the total energy of a system remains constant. This is an important concept to remember when dealing with energy problems. The two basic forms of energy that we will focus on are kinetic energy and potential energy.

Explanation:

In physics and chemistry, the law of conservation of energy states that the total energy of an isolated system remains constant; it is said to be conserved over time. This law means that energy can neither be created nor destroyed; rather, it can only be transformed or transferred from one form to another.

Im bad at these questions hope it helps and have a good day.

8 0

3 years ago