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egoroff_w [7]
3 years ago
6

What is first and second element of the periodic table?

Chemistry
2 answers:
stira [4]3 years ago
7 0
The elements on the periodic table are listed in increasing atomic number. 

Hydrogen is the first element, and has an A.N. of 1. Also, its very interesting how it doesn't need 8 valence electrons to be stable. 

The second element is Helium, which has an A.N (atomic number) of two. 
WINSTONCH [101]3 years ago
6 0

Hydrogen= First element,H

Helium=Second Element,He


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vladimir1956 [14]

Answer:

109.09°C

Explanation:

Given that:

the capacity of the cooling car system = 5.6 gal

volume of solute = volume of the water; since a 50/50 blend of engine coolant and water (by volume) is used.

∴ \frac{5.60}{2}gallons = 2.80 gallons

Afterwards, the mass of the solute and the mass of the water can be determined as shown below:

mass of solute = (M__1}) = Density*Volume

                          = 1.1g/mL *2.80*\frac{3785.41mL}{1gallon}

                         = 11659.06grams

On the other hand; the mass of water = (M__2})= Density*Volume

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                        = 10577.95 grams

Molarity = \frac{massof solute*1000}{molarmassof solute*massofwater}

              =  \frac{11659.06*1000}{62.07*10577.95}

              = 17.757 m

              ≅ 17.76 m

∴  the boiling point of the solution is calculated using the  boiling‑point elevation constant for water and the Molarity.

\Delta T_{boiling} = k_{boiling}M

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k_{boiling} = 0.512 °C/m

\Delta T_{boiling} =  100°C + 17.56 × 0.512

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6 0
3 years ago
What is the equation for figuring out the Atomic Mass
zhenek [66]

Answer:

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I hope this helps! :)

8 0
2 years ago
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Answer:

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Explanation:

5 0
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A trial of this decomposition experiment, using different quantities of reactants than those listed in the question above produc
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Explanation :

Combined gas law is the combination of Boyle's law, Charles's law and Gay-Lussac's law.

The combined gas equation is,

\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}

where,

P_1 = initial pressure of O_2 gas = (740-22.4) torr = 717.6 torr

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Now put all the given values in the above equation, we get:

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5 0
3 years ago
How many salt and water would you use to prepare 10% salt solution?
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Answer:

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Explanation:

have a good day

4 0
2 years ago
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