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3 years ago

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How did Mendeleev arrange the elements in the first periodic table? In order of increasing atomic mass. In order of decreasing a

tomic mass. In order of increasing melting points and densities. In order of increasing atomic number.

1 answer:

hammer [34]3 years ago

7 0

Answer:

Mendeleev arranged the elements on the first periodic table by Increasing atomic mass

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Kp for the reaction CO2(g) + C(s) --- 2CO(g) is 1.47 at 727°C. Calculate Kc at this temperature.

Neko [114]

Answer:

The correct answer is "0.0179".

Explanation:

The given reaction is:

⇒ $CO_2(g) + C(s) \rightleftharpoons 2 \ CO(g)$

The given value is:

At 727°C temperature,

Kp = 1.47

As we know,

Gas constant,

R = 0.0821 L atm/mol.K

Temperature,

= $727+273$

= $1000 \ K$

Now,

The change in moles will be:

⇒ $\Delta n=Products-reactants$

⇒ $=2-1$

⇒ $=1$

As we know,

⇒ $K_p=K_c(RT)^{\Delta n}$

On substituting the given values, we get

⇒ $1.47=K_c(0.0821\times 1000)^1$

⇒ $K_c=\frac{1.47}{0.0821\times 1000}$

⇒ $=\frac{1.47}{82.1}$

⇒ $=0.0179$

8 0

2 years ago

Which tool gives scientists information about the wind speed and humidity of a region?

frez [133]

Answer:

Anemometer. An anemometer is a type of weather instrument that measures wind speed.

6 0

3 years ago

Select the correct answer.

Svetradugi [14.3K]

Answer:

the answer is A

Explanation:

According to the law of conservation of energy or the first law thermodynamics energy neither be created nor destroyed, energy is transferred from one form to another form.

4 0

3 years ago

The combustion of 3.795 mg of liquid B, which contains only C, H, and O, with excess oxygen gave 9.708 mg of CO2 and 3.969 mg of

attashe74 [19]

Answer:

Explanation:

9.708 mg of CO₂ will contain 12 x 9.708 / 44 = 2.64 g of C .

3.969 mg of H₂O will contain 2 x 3.969 / 18 = .441 g of H .

mg of O in given liquid B = 3.795 - ( 2.64 + .441 ) = .714 mg

ratio of mg of C , H , O in the compound = 2.64 : .441 : .714

ratio of no of atoms of C , H , O in the compound

= 2.64 / 12 : .441 /1 : .714 / 16

= .22 : .44 : .0446

= .22 / .22 : .44 / .22 : .044 / .22

= 1 : 2 : .2

1 x 5 : 2 x 5 : .2 x 5

= 5 : 10 : 1

empirical formula of the compound = C₅H₁₀O

Volume of 89.8 mL at 1 .00 atm at 200⁰C

volume of gas at 1 atm and 0⁰C = 89.8 x 273 / 473 mL

= 51.83 mL

51.83 mL weighs .205 g

22400 mL will weigh .205 x 22400 / 51.83 g

= 88.6 g

So molecular weight = 88.6

Let molecular formula be (C₅H₁₀O)ₙ

molecular weight = n ( 5 x 12 + 10 + 16 )

= 86 n

86 n = 88.6

n = 1 approx

So molecular formula is same as empirical formula

C₅H₁₀O is molecular formula .

6 0

2 years ago

Hydrazine (N2H4), a rocket fuel , reacts with oxygen to form nitrogen gas and water vapor. The reaction is represented with the

Archy [21]

i think the answer is 1.56mol H2O

8 0

2 years ago