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3 years ago

Which element has the electron configuration [Xe] 6s2 4f14 5d10 6p2?

1 answer:

4 0

To determine the element that has an electron configuration of [Xe] 6s2 4f14 5d10 6p2, we must know the atomic number of Xe. From the periodic table, Xe has an atomic number of 54. We add the proceeding electrons, which is now a total of 82. The element with this atomic number is lead, Pb.

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For the reaction A(g)

zubka84 [21]

Answer:

Yes

Explanation:

By definition, the equilibrium constanct, Kc, for the reaction A ⇒ 2B is

= [A]^1 / [B]^2

Substitute [A] = 4 and [B] = 2 in the equation,

[A]^1 / [B]^2

= 4^1 / 2^2

= 1

= Kc

So yes the reaction is at equilibrium.

6 0

2 years ago

Barium sulfate is made by the following reaction.

ipn [44]

Answer:

%age Yield = 96 %

Explanation:

The balance chemical equation for given double replacement reaction is,

Ba(NO₃)₂ + Na₂SO₄ → BaSO₄ + 2 NaNO₃

Step 1: Calculate moles of Ba(NO₃)₂:

Moles = Mass / M.Mass

Moles = 75.1 g / 261.33 g/mol

Moles = 0.2873 moles of Ba(NO₃)₂

Step 2: Find out moles of BaSO₄ formed:

According to balance chemical equation,

1 mole of Ba(NO₃)₂ produced = 1 mole of BaSO₄

So,

0.2873 moles of Ba(NO₃)₂ will produce = X moles of BaSO₄

Solving for X,

X = 0.2873 mol × 1 mol / 1 mol

X = 0.2873 moles of BaSO₄

Step 3: Calculate Theoretical Mass of BaSO₄:

Mass = Moles × M.Mass

Mass = 0.2873 mol × 233.38 g/mol

Mass = 67.07 g of BaSO₄

Step 4: Calculate %age Yield as:

Theoretical Yield = 67.07 g

Actual Yield = 64.4 g

%age Yield = ???

Formula Used:

%age Yield = (Actual Yield ÷ Theoretical Yield) × 100

Putting Values,

%age Yield = (64.4 g ÷ 67.07 g) × 100

%age Yield = 96.01 % ≈ 96 %

6 0

2 years ago

Help me I need to know how do do this or just give me answers lol

Pani-rosa [81]

4. 2Li + 2H2O -> 2LiOH + H2
5. C6H12O6 + 6O2 -> 6CO2 + 6H2O
6. Zn + 2HCl -> ZnCl2 + H2
9. H2SO4 + Pb -> PbSO4 + H2
10. Ca(OH)2 + NH4Cl -> NH4 + CaCl2 + H2O
thats all i know

5 0

3 years ago

How many moles are present in 2.126 g of H2O2 ?

Vinil7 [7]

Answer:

molecular weight of H2O2 or grams. This compound is also known as Hydrogen Peroxide. The SI base unit for amount of substance is the mole. 1 mole is equal to 1 moles H2O2, or 34.01468 grams.

1 grams H2O2 is equal to 0.029399071224542 mole.

1 grams H2O2 to mol = 0.0294 mol

10 grams H2O2 to mol = 0.29399 mol

20 grams H2O2 to mol = 0.58798 mol

30 grams H2O2 to mol = 0.88197 mol

40 grams H2O2 to mol = 1.17596 mol

50 grams H2O2 to mol = 1.46995 mol

100 grams H2O2 to mol = 2.93991 mol

200 grams H2O2 to mol = 5.87981 mol

6 0

3 years ago

Read 2 more answers

How many grams of NaF should be added to 500 mL of a 0.100 M solution of HF to make a buffer with a pH of 3.2

Korolek [52]

Answer:

2.25g of NaF are needed to prepare the buffer of pH = 3.2

Explanation:

The mixture of a weak acid (HF) with its conjugate base (NaF), produce a buffer. To find the pH of a buffer we must use H-H equation:

pH = pKa + log [A-] / [HA]

Where pH is the pH of the buffer that you want = 3.2, pKa is the pKa of HF = 3.17, and [] could be taken as the moles of A-, the conjugate base (NaF) and the weak acid, HA, (HF).

The moles of HF are:

500mL = 0.500L * (0.100mol/L) = 0.0500 moles HF

Replacing:

3.2 = 3.17 + log [A-] / [0.0500moles]

0.03 = log [A-] / [0.0500moles]

1.017152 = [A-] / [0.0500moles]

[A-] = 0.0500mol * 1.017152

[A-] = 0.0536 moles NaF

The mass could be obtained using the molar mass of NaF (41.99g/mol):

0.0536 moles NaF * (41.99g/mol) =

<h3>2.25g of NaF are needed to prepare the buffer of pH = 3.2</h3>

4 0

2 years ago