1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
lesantik [10]
3 years ago
15

Use the periodic table to determine the electron configuration for Ca and Pm in noble-gas notation Ca: [Ar]4s2 [Ar]4s1 [Ar]3s2 [

Kr]4s2
Chemistry
2 answers:
sveta [45]3 years ago
5 0
Answer:

1) Ca: [Ar]4s²
2) Pm: [Xe]6s²4f⁵

Explanation:

1) Ca:

Its atomic number is 20. So it has 20 protons and 20 electrons.

Since it is in the row (period) 4 the noble gas before it is Ar, and the electron configuration is that of Argon whose atomic number is 18.

So, you have two more electrons (20 - 18 = 2) to distribute.

Those two electrons go the the orbital 4s.

Finally, the electron configuration is [Ar] 4s².

2) Pm

The atomic number of Pm is 61, so it has 61 protons and 61 electrons.

Pm is in the row (period) 6. So, the noble gas before Pm is Xe.

The atomic number of Xe is 54.

Therefore, you have to distribute 61 - 54 = 7 electrons on the orbitals 6s and 4f.

The resultant distribution for Pm is: [Xe]6s² 4f⁵.
Pepsi [2]3 years ago
4 0

Answer:

Ca:

[Ar]4s2

Explanation:

jus did it

You might be interested in
2) __H,PO, +
Gnoma [55]

Explanation:

a.H2PO4 + 2KOH = K2PO4 + 2H2O

b. H2PO4 _ 2KOH

1(2) + 31 + 16(4) _ 2(23) + 2(16) + 2(1)

2 + 31 + 64 _ 46 + 32 + 2

97 _ 80

no of moles of H2PO4 = 2.5 ÷ 97

= 0.026mol

no of moles of 2KOH = 4 ÷ 80

= 0.05mol

2KOH is the limiting reactant

c. H2PO4 is the excess reactant

d. 1 mole H2PO4 weighs 2.5g

0.026mol H2PO4 weighs g

(0.026 × 2.5)

H2PO4 weighed 0.065g after reaction

4 0
4 years ago
What is one energy transformation that is taking place in the photo?
Galina-37 [17]

I'm guessing the photo means photosynthesis. In that case, it is solar energy to chemical energy. Radiant energy and solar energy is kind of the same thing, so 4th answer.

4 0
3 years ago
Read 2 more answers
Name the particle discovered by James<br> Chadwick in 1932.
LenKa [72]

Answer:

He discovered neutrons in 1932

4 0
3 years ago
For the reaction 2k(s)+br2(l)→2kbr(s) calculate how many grams of the product form when 21.4 g of br2 completely reacts. assume
Neko [114]
The balanced equation for the above reaction is as follows;
2K + Br₂ --> 2KBr 
Stoichiometry of Br₂ to KBr is 1:2
we have been told that K is present which means that Br₂ is the limiting reactant. Limiting reactant is the reactant that is fully consumed in the reaction and amount of product formed depends on amount of limiting reactant present.
Number of Br moles reacted - 21.4 g / 160 g/mol = 0.134 mol
According to stoichiometry, 
1 mol of Br₂ forms 2 mol of KBr 
therefore 0.134 mol of Br₂ forms 2x0.134 = 0.268 mol of KBr
mass of KBr formed - 0.268 mol x 119 g/mol = 31.9 g of KBr
 a mass of 31.9 g of KBr is formed 
7 0
3 years ago
Energy is just like any other chemical or physical process, where it cannot be created or destroyed. Which Law states this fact?
Studentka2010 [4]
The answer should be law of conservation of energy
3 0
3 years ago
Other questions:
  • Integrated Problem 01.69 With current spectroscopic techniques, chemists are generally able to determine the structure of an unk
    13·1 answer
  • What is the chemica composition if the sun
    6·2 answers
  • Correct name for LiCl
    6·1 answer
  • Approximately what percentage of the weight of the human body is water?
    8·2 answers
  • Based on the properties of the compounds in the interactive, predict whether the given compounds behave as electrolytes or as no
    9·1 answer
  • The exact position of the electrons of an atom cannot be determined because they are in constant ___
    12·1 answer
  • Which intermolecular force would affect the boiling point the least?
    11·2 answers
  • (g) How does the colour of a star help to find its age?
    14·1 answer
  • The brightness of a star as seen from Earth is referred to as (.......) brightness. what is the word I can't remember it
    8·1 answer
  • Carlos is making phosphorus trichloride using the equation below.
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!