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3 years ago

What is the name of the phase where stars live out most of their lives?

1 answer:

8 0

The correct option is B.
Stars live out most of their lives at MAIN SEQUENCE. Stars generally are divided into three major stages, these are:
1. Pro stars and pre-main sequence star
2. Main sequence and giant star
3. Variable stars
Major stages in the life of a star can last for millions of years.

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In which or areas on the image dose salinity of the ocean increases

Ronch [10]

Answer and Explanation:

D I believe..

8 0

2 years ago

A serving of soup contains 5.0 g of fat, 20.0 g of carbohydrates, and 3.0 g of protein. Determine how many kilocalories (kcal) a

marta [7]

Answer: The amount of kilocalories contained in the given serving of soup is 0.137 kCal

Explanation:

As per the USDA:

Carbohydrates provide 4 calories per gram, protein provides 4 calories per gram, and fat provides 9 calories per gram.

We are given

Mass of fat in the soup serving = 5.0 g

Mass of carbohydrates in the soup serving = 20.0 g

Mass of protein in the soup serving = 3.0 g

Conversion factor used: 1 kCal = 1000 Cal

Applying unitary method:

For Fat:

1 gram of fat provides 9 calories

So, 5.0 gram of fat will provide = $\frac{9}{1}\times 5.0=45Cal=0.045kCal$

For Carbohydrates:

1 gram of carbohydrates provides 4 calories

So, 20.0 gram of carbohydrates will provide = $\frac{4}{1}\times 20.0=80Cal=0.080kCal$

For Proteins:

1 gram of proteins provides 4 calories

So, 3.0 gram of fat will provide = $\frac{4}{1}\times 3=12Cal=0.012kCal$

Total kilocalories per serving = [0.045 + 0.080 + 0.012] kCal = 0.137 kCal

Hence, the amount of kilocalories contained in the given serving of soup is 0.137 kCal

4 0

3 years ago

How many moles of CO2 are emitted into the atmosphere when 22.1 g C8H18 is burned

ANTONII [103]

Answer:

1.552 moles

Explanation:

First, we'll begin by writing a balanced equation for the reaction showing how C8H18 is burn in air to produce CO2.

This is illustrated below:

2C8H18 + 25O2 -> 16CO2 + 18H2O

Next, let us calculate the number of mole of C8H18 present in 22.1g of C8H18. This is illustrated below:

Molar Mass of C8H18 = (12x8) + (18x1) = 96 + 18 = 114g/mol

Mass of C8H18 = 22.1g

Mole of C8H18 =..?

Number of mole = Mass /Molar Mass

Mole of C8H18 = 22.1/144

Mole of C8H18 = 0.194 mole

From the balanced equation above,

2 moles of C8H18 produced 16 moles of CO2.

Therefore, 0.194 mole of C8H18 will produce = (0.194x16)/2 = 1.552 moles of CO2.

Therefore, 1.552 moles of CO2 are emitted into the atmosphere when 22.1 g C8H18 is burned

8 0

2 years ago

What does (I) means in a chemical equation

Svetllana [295]

Answer:

the l sign means the substance in the chemical equation is a liquid. (hope this helped : D )

6 0

2 years ago

Using your data above, draw conclusions about the d-splitting for each ligand (H2O, en, phen). Order the complexes from least to

Delvig [45]

Answer:

H2O<en<phen

Explanation:

The degree of d- splitting is observed from the intensity of colour. The order of d splitting from least to greatest is H2O<en<phen. Phen shows the greatest d-splitting. The degree of splitting of d- orbitals by ligands depends on their relative positions in the spectrochemical series. The spectrochemical series is an experimentally determined series. The series separates the ligands into strong field and weak field ligands. Strong field ligands are found towards the end of the series. Strong field ligands such as en and phen can participate in metal to ligand or ligand to metal pi-bonding. Hence they cause more d-splitting. Ethylendiamine and phenanthroline occur towards the end of the spectrochemical series hence the higher order of d-splitting.

7 0

2 years ago