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qwelly [4]
3 years ago
5

The first periodic table of elements was created in 1955. True or false

Chemistry
1 answer:
DaniilM [7]3 years ago
5 0
I believe the answer is false
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What is the position of the element ammonia in periodic table?
Rashid [163]
Ammonia isn't an element, it's a compound made by mixing the elements Nitrogen and Hydrogen in the Haber process. Therefore, it isn't on the periodic table
8 0
3 years ago
Read 2 more answers
Calculate number of moles of 4.4g of CO2 and 5.6L of NH3 . Pls help . Its urgent
kupik [55]
Moles of CO₂ = mass / molecular weight
Moles of CO₂ = 4.4 / (12 + 16 x 2)
Moles of CO₂ = 0.1 mol

Each mole of gas occupies 22.4 L at STP. Therefore,
Moles of NH₃ = 5.6 / 22.4
Moles of NH₃ = 0.25 mol
4 0
4 years ago
Ammonia, NH3 is a common base with Kb of 1.8 X 10-5. For a solution of 0.150 M NH3:
Vesnalui [34]

The concentrations : 0.15 M

pH=11.21

<h3>Further explanation</h3>

The ionization of ammonia in water :

NH₃+H₂O⇒NH₄OH

NH₃+H₂O⇒NH₄⁺ + OH⁻

The concentrations of all species present in the solution = 0.15 M

Kb=1.8 x 10⁻⁵

M=0.15

\tt [OH^-]=\sqrt{Kb.M}\\\\(OH^-]=\sqrt{1.8\times 10^{-5}\times 0.15}\\\\(OH^-]=\sqrt{2.7\times 10^{-6}}=1.64\times 10^{-3}

\tt pOH=-log[OH^-]\\\\pOH=3-log~1.64=2.79\\\\pH=14-2.79=11.21

8 0
3 years ago
Which answer correctly ranks the atoms in terms of decreasing electronegativity (the highest electronegativity first)? which ans
Degger [83]

Answer:

O, N, C, H

Explanation:

Electronegativity of an element is the property that combines the ability of its atom to lose or gain electrons. It measures the relative tendency with which the atoms of the element attracts valence electrons in a chemical bond.

On the periodic table, Electronegativity increases across the period but decreases down a group.

To solve the given problem, let us use thE Pauling's table of electronegativities to compare the electronegativities of the elements.

On the table:

C = 2.5

H = 2.1

O = 3.5

N = 3.0

In terms of decreasing electronegativities, the atoms are arranged as:

O N C H

4 0
3 years ago
Four competitors raced their bicycles in a 1000-meter race. During the last 300 meters, each bicycle was moving with the same sp
tresset_1 [31]

Answer:

stop deleting my answers!!!

Explanation:

7 0
4 years ago
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