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
Lelechka [254]
2 years ago
5

The total number of the elements above with 2 valence electron is ____.

Chemistry
1 answer:
OverLord2011 [107]2 years ago
4 0

Answer:

four elements

Explanation:

He = 1s²

Be = 1s² 2s²

C = 1s² 2s² 2p²

Mg = 1s² 2s² 2p⁶ 3s²

Si = 1s² 2s² 2p⁶ 3s² 3p²

Ca = 1s² 2s² 2p⁶ 3s² 3p⁶ 4s²

Valence electrons are those electrons which are present in outer most electronic shell.

He, Be, Mg, Ca these four elements have 2 valence electrons.

While Si and C have four valance electrons.

You might be interested in
The element in Group 14 Period 4 has how many neutrons and is it a metal, nonmetal, metalloid or noble gas.
monitta

Number of neutrons=41, and it is metalloid

<h3>Further explanation</h3>

Group 14⇒valence electron = 4(ns²np²)

Period 4⇒n=4

So electron configuration of the element :

1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d¹⁰, 4p² = 32 electron=atomic number

The element with atomic number 32, which is in period 4 and group 14 is Ge-Germanium

There are seven elements that can be classified as metalloids, namely boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te), and polonium (Po).

While the mass number: 73

So the number of neutrons = mass number-atomic number

\tt 73-32=41

8 0
2 years ago
Butanol is composed of carbon, hydrogen, and oxygen. If 1.0 mol of butanol contains 6.0 x 1024 atoms of hydrogen, what is the su
yanalaym [24]

Answer:

Option B. 10

Explanation:

If 1 mol of butanol contains 6×10²⁴ atoms of H, let's calculate the amount of H.

(number of atoms  / NA)

6.02 x 10²³ atoms ___ 1 mol

6×10²⁴ atoms will occupy (6×10²⁴ / NA) = 9.96 moles

H, has 10 moles in the butano formula.

4 0
2 years ago
F
kobusy [5.1K]

Answer:

From the periodic table, Atomic number of fluorine is 7 and atomic mass is 19

8 0
2 years ago
What’s a new discovery that makes it easier to use biomass as an energy source?
stellarik [79]

Answer:

Biomass to an Energy source

Explanation:

Researchers have developed a new catalyst that directly converts cellulose, the most common form of biomass, into ethylene glycol, an important intermediate product for chemical industry. Alternatives to fossil fuels and natural gas as carbon sources and fuel are in demand.

6 0
2 years ago
Read 2 more answers
____N2 + ____H2  ____NH3
Fiesta28 [93]

Answer:

N2 + 3H2 + 2NH3

Explanation:

I'm assuming you're balancing the chemical equation

3 0
2 years ago
Read 2 more answers
Other questions:
  • How many grams of carbon dioxide are produced from 0.98 mol of Fe3O4?
    6·1 answer
  • A voltaic cell is created by using a copper cathode and a magnesium anode. The cathode is immersed in a solution of Cu2 ions, an
    8·1 answer
  • How many moles (of molecules or formula units) are in each sample? 79.34 g cf2cl2?
    6·1 answer
  • Why do liquids and gases take the shape of their containers while solids do not?
    12·2 answers
  • The chemical reaction in which solid calcium oxide is treated liquid water is an example of what: A) decomposition B)combustion
    12·1 answer
  • Describe the light spectrum of a star
    15·1 answer
  • 7. How many chlorine atoms are in a 34.2 g sample of dichlorine pentoxide?
    8·1 answer
  • This compound, an eight-carbon alkane, serves as the 100 octane standard for gasoline. It has five methyl groups, one quaternary
    5·1 answer
  • What is called oxidizing agent and reducing agent?
    10·1 answer
  • BASIC CALCULATIONS IN SPECTROSCOPY
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!