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
Gnom [1K]
3 years ago
10

which best describes an element? - a pure substance - a type of a mixture - a pure compound - an impure substance

Chemistry
2 answers:
Nikitich [7]3 years ago
7 0
An element is a pure substance which means it cannot be broken down by any means.
STatiana [176]3 years ago
4 0

Answer:

A pure substance

Explanation:

An element is a pure substance.

It is only made up of atoms of the same type.

You might be interested in
Please help me I will give you extra points and the brain thing please actually do it.
Shkiper50 [21]
Inertia is the retaliation of an object to change in its velocity
4 0
3 years ago
Which term can be used to describe the process in the reaction below? 2 NaHCO3 (s) → Na2CO3 (s) + H2O (g) + CO2 (g)
Setler79 [48]

Answer:

Decomposition

Explanation:

If we look at the process;

2 NaHCO3 (s) → Na2CO3 (s) + H2O (g) + CO2 (g)

We can see that NaHCO3 was broken down into Na2CO3, H2O and CO2.

The breakdown of one compound to yield other chemical compounds is known as decomposition.

Hence the NaHCO3 was decomposed in the process above.

4 0
2 years ago
How can you determine which bond in a structure is more polar without using an electronegativity table?
UkoKoshka [18]
To know this you pretty much do have to kind of memorize a few electronegativities. I don't recall ever getting a table of electronegativities on an exam.
From the structure, you have:

I remember the following electronegativities most because they are fairly patterned:
EN
H
=
2.1
EN
C
=
2.5
EN
N
=
3.0
EN
O
=
3.5
EN
F
=
4.0
EN
Cl
=
3.5
Notice how carbon through fluorine go in increments of
~
0.5
. I believe Pauling made it that way when he determined electronegativities in the '30s.
Δ
EN
C
−
Cl
=
1.0
Δ
EN
C
−
H
=
0.4
Δ
EN
C
−
C
=
0.0
Δ
EN
C
−
O
=
1.0
Δ
EN
O
−
H
=
1.4
So naturally, with the greatest electronegativity difference of
4.0
−
2.5
=
1.5
, the
C
−
F
bond is most polar, i.e. that bond's electron distribution is the most drawn towards the more electronegative compound as compared to the rest.
When the electron distribution is polarized and drawn towards a more electronegative atom, the less electronegative atom has to move inwards because its nucleus was previously favorably attracted to the electrons from the other atom.
That means generally, the greater the electronegativity difference between two atoms is, the shorter you can expect the bond to be, insofar as the electronegative atom is the same size as another comparable electronegative atom.
However, examining actual data, we would see that on average, in conditions without other bond polarizations occuring:
r
C
−
Cl
≈
177 pm
r
C
−
C
≈
154 pm
r
C
−
O
≈
143 pm
r
C
−
F
≈
135 pm
r
C
−
H
≈
109 pm
r
O
−
H
≈
96 pm
So it is not necessarily the least electronegativity difference that gives the longest bond.
Therefore, you cannot simply consider electronegativity. Examining the radii of the atoms, you should notice that chlorine is the biggest atom in the compound.
r
Cl
≈
79 pm
r
C
≈
70 pm
r
H
≈
53 pm
r
O
≈
60 pm
So assuming the answer is truly
C
−
C
, what would have to hold true is that:
The
C
−
F
bond polarization makes the carbon more electropositive (which is true).
The now more electropositive carbon wishes to attract bonding pairs from chlorine closer, thereby shortening the
C
−
Cl
bond, and potentially the
C
−
H
bond (which is probably true).
The shortening of the
C
−
Cl
bond is somehow enough to be shorter than the
C
−
C
bond (this is debatable).
5 0
3 years ago
Read 2 more answers
28. Which set of coefficients will balance this chemical equation?
Makovka662 [10]
2021 hoped I helped you god bless you
5 0
3 years ago
A sample of gas has a volume of 75.0 mL at 30.0 psi. Determine the pressure of the gas if its volume is changed to 15 mL and its
Assoli18 [71]

Answer:

5.995 psi

Explanation:

30 psi = 2.04 atm

75 mL = 0.075 L

15 mL = 0.015 L

0.075 L/ 2.04 atm = 0.015 L/x

0.075x = 0.0306

x = 0.408

0.408 atm = 5.995 psi

4 0
3 years ago
Other questions:
  • HELP!!!
    6·2 answers
  • Why do you need many different indicators to span the entire ph spectrum?
    6·1 answer
  • Someone please help me i’m stuck
    10·1 answer
  • A compound has a chemical composition of 97.6 g carbon, 4.9 g hydrogen, 52 g oxygen, 45.5 g nitrogen. What is the empirical form
    15·1 answer
  • In a certain acidic solution at 25 ∘C, [H+] is 100 times greater than [OH −]. What is the value for [OH −] for the solution?
    10·1 answer
  • What ion is Calcium most likely to form? and how do you know?
    11·1 answer
  • A sample of air is slowly passed through aqueous Sodium hydroxide and then over heater copper.
    6·2 answers
  • 50 points guys please help me!!!!!!
    6·1 answer
  • Question 13 of 25
    12·1 answer
  • Name three different properties you can test before and after a chemical reaction​
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!