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2 years ago

Why is the Milky Way considered a galaxy

Chemistry

2 answers:

Lady bird [3.3K]2 years ago

7 0

Answer: it is

Explanation: A galaxy is a system of millions or billions of stars, together with gas and dust, held together by gravitational attraction, plus there are 100 billion planet in it.

Lady_Fox [76]2 years ago

3 0

Answer:

Explanation:

All the stars we see in the night sky are in our own Milky Way Galaxy. Our galaxy is called the Milky Way because it appears as a milky band of light in the sky when you see it in a really dark area.

You might be interested in

How does temperature, pressure, and density impact the core of the Earth?

Vanyuwa [196]

Answer:

temperatures within the outer core range from 7,200 to 9,000 F. Pressure also increases in the outer core due in part to the weight of the crust and mantle above.The Earth's magnetic field is generated by the outer core.

Explanation:

4 0

3 years ago

Francium is an extremely rare alkali metal, many of whose physical properties

bazaltina [42]

Answer:

136 neutrons

87 protons

Explanation:

A neutral atom have equal number of protons and neutrons. In other words we can say that negative and positive charges are equal in magnitude and cancel the each other. For example if neutral atom has 6 protons than it must have 6 electrons. The number of protons or number of electrons are the atomic number of an atom while the number of protons and number of neutrons are the mass number of an atom. Every atom consist of nucleus or a positive center. The protons and neutrons are present with in the nucleus while electrons are present out side the nucleus. All these three subatomic particles construct an atom.

Example:

In Francium the number of proton and neutron can be found by subtracting the atomic number of francium from its atomic mass. The atomic number will be the number of protons and remaining will show the total number of neutrons present in nucleus.

Atomic number is 87

Atomic mass 223

223- 87 = 136

So number of neutrons are 136 and number of protons are 87.

6 0

3 years ago

What describes the proton

stellarik [79]

The proton is the positively charged sub-atomic particle in the nucleus of an atom and the electron is the negatively charged P for positive.

6 0

3 years ago

Please help me!!!30 pts

Tanya [424]

Answer:

Question 7 to 12 are given in attached file because character limit is only 5000

Explanation:

1. A 15.0 gram sample of a compound is found to contain 8.83 grams of sodium and 6.17 grams of sulfur. Calculate the empirical formula of this compound.

Given data:

Mass of sample = 15 g

Mass of sodium = 8.83 g

Mass of sulfur = 6.17 g

Empirical formula = ?

Solution:

Number of gram atoms of Na = 8.83 / 23 = 0.4

Number of gram atoms of S = 6.17 / 32 = 0.2

Atomic ratio:

Na : S

0.4/0.2 : 0.2/0.2

2 : 1

Na : S = 2 : 1

Empirical formula is Na₂S.

2. Analysis of a 10.150 gram sample of a compound known to contain only phosphorus and oxygen indicates a phosphorus content of 4.433 grams. What is the empirical formula of this compound?

Given data:

Mass of phosphorus = 4.433 g

Mass of oxygen = 10.150 g - 4.433 g = 5.717 g

Empirical formula = ?

Solution:

Number of gram atoms of P = 4.433 / 30.9738 = 0.1431

Number of gram atoms of O = 5.717/ 15.999 = 0.3573

Atomic ratio:

P : O

0.1431/0.1431 : 0.3573/0.1431

1 : 2.5

P : O = 2(1 : 2.5)

Empirical formula is P₂O₅.

3. A compound is found to contain 36.48%Na, 25.41% S, and 38.11% O. Find its empirical formula.

Given data:

Percentage of sodium = 36.48%

Percentage of sulfur = 25.41%

Percentage of oxygen = 38.11%

Empirical formula = ?

Solution:

Number of gram atoms of Na = 36.48 / 23 = 1.6

Number of gram atoms of S = 25.41/ 32 = 0.8

Number of gram atoms of O = 38.11/ 16 = 2.4

Atomic ratio:

Na : S : O

1.6/0.8 : 0.8/0.8 : 2.4/0.8

2 : 1 : 3

Na: S : O = 2 : 1 : 3

Empirical formula is Na₂SO₃.

4. A compound is found to contain 63.52% iron and 36.48% sulfur. Find its empirical formula.

Given data:

Percentage of iron = 63.52%

Percentage of sulfur = 36.48%

Empirical formula = ?

Solution:

Number of gram atoms of Fe = 63.52 / 55.845 = 1.14

Number of gram atoms of S = 36.48 / 32 = 1.14

Atomic ratio:

Fe : S

1.14/1.14 : 1.14/1.14

1 : 1

Fe : S = 1 : 1

Empirical formula is FeS.

5. Qualitative analysis shows that a compound contains 32.38%sodium, 22.65% sulfur and 44.99 % oxygen. Find the empirical formula of this compound.

Given data:

Percentage of sodium = 32.38%

Percentage of sulfur = 22.65%

Percentage of oxygen = 44.99%

Empirical formula = ?

Solution:

Number of gram atoms of Na = 32.38 / 23 = 1.4

Number of gram atoms of S = 22.65/ 32 = 0.7

Number of gram atoms of O = 44.99/ 16 = 2.8

Atomic ratio:

Na : S : O

1.4/0.7 : 0.7/0.7 : 2.8/0.7

2 : 1 : 4

Na: S : O = 2 : 1 : 4

Empirical formula is Na₂SO₄.

6. Analysis of a 20.0 gram sample of a compound containing only calcium and bromine indicates that 4.00 grams of calcium are present. What is the empirical formula of the compound formed?

Given data:

Mass of sample = 20g

Mass of bromine = 20 g - 4 g = 16 g

Mass of calcium = 4 g

Empirical formula = ?

Solution:

Number of gram atoms of bromine = 16 / 80= 0.2

Number of gram atoms of calcium = 4/ 40= 0.1

Atomic ratio:

Ca : Br

0.1/0.1 : 0.2/0.1

1 : 2

Ca: Br = 1 : 2

Empirical formula is CaBr₂.

5 0

3 years ago

Read 2 more answers

Why is citric acid added to food?

dolphi86 [110]

Answer: Option (b) is the correct answer.

Explanation:

Chemical formula of citric acid is $C_{6}H_{8}O_{7}$ .

It is acidic in nature and therefore, it is used to add tartness or sour flavor to the food like jams, jellies, candies etc.

It is also used as a preservative and thus it helps to preserve various food items for a longer period of time.

3 0

3 years ago

Read 2 more answers