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
san4es73 [151]
3 years ago
13

Which sign is NOT for a chemical change?

Chemistry
2 answers:
Alik [6]3 years ago
8 0
B is not a sign for chemical change
erastovalidia [21]3 years ago
8 0

Answer:c

Explanation:

You might be interested in
John dalton proposed a theory that all matter is made up of individuals particles which cannot be divided. what were those parti
juin [17]
The particles are atoms, his theory is the atomic theory
3 0
3 years ago
A 251 ml sample of 0.45M HCl is added to 455 mL of distilled water. What is the molarity of the
Oksi-84 [34.3K]

<u>We are given:</u>

251 mL sample of 0.45M HCl added to 455 mL distilled water

<u>Whack a mole! (finding the number of moles):</u>

We know that in order to find molarity, we use the formula:

Molarity = number of moles / Volume (in L)

so, number of moles is:

Number of moles = Molarity * Volume(in L)

now let's plug the values for the HCl solution to find the number of moles

Number of moles = 0.45M * 0.251 L

Number of moles = 0.113 moles

<u>Time to concentrate (finding the final concentration):</u>

Total final volume = 251 mL + 455 mL = 706 mL = 0.706 L

Number of moles of HCl = 0.113 moles

Molarity = Number of moles / Volume (in L)

Molarity = 0.113 / 0.706

Molarity = 0.16 M

___________________________________________________________

<u>BONUS METHOD TIME!!!</u>

We know the relation:

M1 * V1 = M2 * V2

where M1 and M2 are the initial and final molarities and V1 and V2 are initial and final volumes respectively

notice that I didn't mention that the volume has to be in Liters, that's because of the units being concerned with both sides of the equation, say I have the volume in mL and want to convert both these volumes to L, I would divide both sides by 1000, which would NOT change the overall value

Now, plugging values in this equation

(0.45) * (251) = (251 + 455)* (M2)

112.95 = (706)(M2)

M2 = 112.97/706                                [dividing both sides by 706]

M2 = 0.16 Molar

8 0
2 years ago
lassify these bonds as ionic, polar covalent, or nonpolar covalent. Ionic Polar covalent Nonpolar covalent
jarptica [38.1K]

The question is incomplete, complete question is:

Classify these bonds as ionic, polar covalent, or nonpolar covalent.

Na-F

P-Cl

Cl-Cl

Answer:

Na-F  : The bond present is ionic bond.

PCl  : The bond present is polar covalent bond.

ClCl  : The bond present is non polar covalent bond.

Explanation:

1) Ionic bonds are defined as the bonds which are formed by the complete transfer of electrons from cation (positively charged ions) to anion (negatively charged ions). For Example: NaCl, BaSO_4 etc.

Ionic compound :This compound is formed when difference in electronegativity between the atoms is very large.

2) Covalent bond is defined as the bond which is formed by the sharing of electrons between the atoms. For Example: HCl, CH_4 etc.

Polar covalent compound: This compound is formed when difference in electronegativity between the atoms is present. When atoms of different elements combine, it results in the formation of polar covalent bond. For Example: CO_2,NO_2 etc..

Non-polar covalent compound: This compound is formed when there is no difference in electronegativity between the atoms. When atoms of the same element combine, it results in the formation of non-polar covalent bond. For Example: N_2,O_2 etc.

Na-F  : Two different atoms with high electronegativity difference

Ionic compound because sodium is metal and fluorine is non metal and the difference between their electronegativity is very large.The bond present is ionic bond.

PCl  : Two different atoms with low electronegativity difference

Polar covalent  compound because phosphorus and fluorine both are non metal and the difference between their electronegativity is not very large.The bond present is polar covalent bond.

ClCl  : Two same atoms with nil electronegativity difference.

Non Polar covalent compound because both are chlorine atom (non metal) and the difference between their electronegativity is zero.The bond present is non polar covalent bond.

5 0
2 years ago
A sample of gas starts at 1.00 atm, 0.00 degrees Celsius, and 30.0 mL. What is the
lara31 [8.8K]

Answer:

pV= nRT

Explanation:

(p1 × V1)/ T1/ (p2 × V2)/ T2

4 0
2 years ago
Which of these is the lowest subgroup? kingdom, order, genus, or species.
olga55 [171]
The correct answer is species

6 0
3 years ago
Read 2 more answers
Other questions:
  • (02.03 MC)
    12·1 answer
  • What type of reaction is A + B + heat → C + D
    8·1 answer
  • A weather map is an example of a
    10·2 answers
  • Easy Question! Chemistry - Please help! I give thanks - It's the picture - Question 2
    12·1 answer
  • Light shining on a strip of metal can dislodge electrons. Do you think this is more consistent with light being made up of waves
    5·2 answers
  • You can purchase hydrochloric acid in a concentrated form that is 37.0% HCl by mass and that has a density of 1.20 g/mL. Describ
    11·1 answer
  • Which two elements have the most similar chemical properties?
    12·2 answers
  • 1.
    9·1 answer
  • Consider the reaction. X ( g ) + Y ( g ) − ⇀ ↽ − Z ( g ) K p = 1.00 at 300 K In which direction will the net reaction proceed fo
    13·1 answer
  • How many grams of water were produced
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!