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2 years ago

Which phrase describes an irregular galaxy?

Chemistry

2 answers:

TiliK225 [7]2 years ago

4 0

Answer:

the answer is b

Explanation:

Stels [109]2 years ago

3 0

Answer: The answer would be B. contains many young stars.

Explanation:

There is very little new star formation in Irregular galaxies. Irregular galaxies have no particular shape and are smaller than other types of galaxies.

You might be interested in

Why is alchemy not considered a science

Dima020 [189]

That is because Alchemy is not based on real research and facts, but rather on magic and occultism. Sure, many things in it have been used as basics for some chemistry, but most is false and incorrect.

6 0

2 years ago

A 45.0-gram sample of copper metal was heated from 20.0°C to 100.0°C. Calculate the heat absorbed, in kJ, by the metal.

s2008m [1.1K]

Answer:

1.386 KJ

Explanation:

From the question given above, the following data were obtained:

Mass (M) of copper = 45 g

Initial temperature (T1) = 20.0°C

Final temperature (T2) = 100.0°C

Heat absorbed (Q) =..?

Next, we shall determine the change in temperature. This can be obtained as follow:

Initial temperature (T1) = 20.0°C

Final temperature (T2) = 100.0°C

Change in temperature (ΔT) =?

ΔT = T2 – T1

ΔT = 100 – 20

ΔT = 80 °C

Next, we shall determine the heat absorbed by the sample of copper as follow:

Mass (M) of copper = 45 g

Change in temperature (ΔT) = 80 °C

Specific heat capacity (C) of copper = 0.385 J/gºC

Heat absorbed (Q) =..?

Q = MCΔT

Q = 45 × 0.385 × 80

Q = 1386 J

Finally, we shall convert 1386 J to KJ. This can be obtained as follow:

1000 J = 1 KJ

Therefore,

1386 J = 1386 J × 1 KJ /1000 J

1386 J = 1.386 KJ

Thus, the heat absorbed by the sample of the sample of copper is 1.386 KJ.

5 0

2 years ago

QUESTION 17

borishaifa [10]

Question 17:

False; cutting hair would change what it looks like but, braiding it keeps it the same substance it is.

Question 18 :

My best guess would either be A or D. I would lean more towards D because if there are different mixtures then it depends on what you are mixing.

Hope it helps in some way. <3

5 0

2 years ago

An unknown amount of mercury (II) oxide was decomposed in the lab. Mercury metal was formed and 5.20 L of oxygen was released at

Yakvenalex [24]

Answer:

68.3g

Explanation:

1. Word equation:

mercury(II) oxide → mercury + oxygen

2. Balanced molecular equation:

2HgO → 2Hg + O₂(g)

3. Mole ratio

Write the ratio of the coefficients of the substances that are object of the problem:

$2molHgO/1molO_2$

4. Calculate the number of moles of O₂(g)

Use the equation for ideal gases:

$pV=nRT\\\\\\n=\dfrac{pV}{RT}\\\\\\n=\dfrac{0.970atm\times5.20L}{0.08206atm.L/K.mol\times 390.0K}\\\\\\n=0.1576mol$

5. Calculate the number of moles of HgO

$\dfrac{2molHgO}{1molO_2}\times 0.1576molO_2=0.315molHgO$

6. Convert to mass

mass = # moles × molar mass

molar mass of HgO: 216.591g/mol

mass = 0.315mol × 216.591g/mol = 68.3g

7 0

2 years ago

A chemist prepares a solution of magnesium chloride MgCl2 by measuring out 49.mg of MgCl2 into a 100.mL volumetric flask and fil

Flura [38]

Answer: Molarity of $Cl^-$ anions in the chemist's solution is 0.0104 M

Explanation:

Molarity : It is defined as the number of moles of solute present per liter of the solution.

Formula used :

$Molarity=\frac{n\times 1000}{V_s}$

where,

n= moles of solute

$Moles=\frac{\text{Given mass}}{\text{Molar mass}}=\frac{0.049g}{95g/mol}=5.2\times 10^{-4}moles$

$V_s$ = volume of solution in ml = 100 ml

Now put all the given values in the formula of molarity, we get

$Molarity=\frac{5.2\times 10^{-4}moles\times 1000}{100ml}=5.2\times 10^{-3}mole/L$

Therefore, the molarity of solution will be $5.2\times 10^{-3}mole/L$

$MgCl_2\rightarrow Mg^{2+}+2Cl^-$

As 1 mole of $MgCl_2$ gives 2 moles of $Cl^-$

Thus $5.2\times 10^{-3}$ moles of $MgCl_2$ gives = $\frac{2}{1}\times 5.2\times 10^{-3}=0.0104$

Thus the molarity of $Cl^-$ anions in the chemist's solution is 0.0104 M

6 0

2 years ago