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
nasty-shy [4]
3 years ago
5

How many significant figures does .150, 20.20, and 25.00 have?

Chemistry
1 answer:
viva [34]3 years ago
6 0
.150 = 3
20.20 = 4
25.00 = 4
If a 0 does not have a number or a period after it, it is not significant.
If the 0 is behind the decimal point, it is always significant.
You might be interested in
What is the meaning of the word solubility
LekaFEV [45]
Amount of a substance (called the solute) that dissolves in a unit volume of a liquid substance (called the solvent) to form a saturated solution under specified conditions of temperature and pressure.Solubility is expressed usually as moles of solute per 100 grams of solvent.
3 0
2 years ago
Read 2 more answers
For the galvanic (voltaic) cell Fe(s) + Mn2+(aq) → Fe2+(aq) + Mn(s) (E°= 0.77 V at 25°C), what is [Fe2+] if [Mn2+] = 0.040 M and
avanturin [10]

Answer:

0.01836 M

Explanation:

Again the reaction equation is;

Fe(s) + Mn2+(aq) → Fe2+(aq) + Mn(s)

E°cell= 0.77 V

Ecell= 0.78 V

[Mn2+] = 0.040 M

[Fe2+] = the unknown

n=2

From Nernst's equation;

Ecell= E°cell- 0.0592/n log Q

0.78= 0.77 - 0.0592/2 log [Fe2+] /[0.040]

0.78-0.77= - 0.0592/2 log [Fe2+] /[0.040]

0.01/ -0.0296= log [Fe2+] /[0.040]

-0.3378= log [Fe2+] /[0.040]

Antilog(-0.3378) = [Fe2+] /[0.040]

0.459= [Fe2+] /[0.040]

[Fe2+] = 0.459 × 0.040

[Fe2+] = 0.01836 M

7 0
3 years ago
Which units are used to measure both velocity and speed? Select three options
Ede4ka [16]

Answer and Explanation:

The options aren't listed in your question, but here are some units that are regularly and normally used (in the classroom and in the outside world):

(The SI unit of distance and displacement is the meter. The SI unit of time is the second.)

<u>Meters per Second (m/s)</u>

kilometers per hour (km/hr)

kilometers per second (km/sec)

To find the average speed, you do distance divided by time.

To find the average velocity, you do the final position minus the initial position, divided by the final time minus the initial time.

<em><u>#teamtrees #PAW (Plant And Water)</u></em>

<em><u></u></em>

<em><u>I hope this helps!</u></em>

8 0
3 years ago
What cause the ratio of PV/RT to drop below 1 when 1 mole of
pentagon [3]

Answer:

pressure and temperature are directly proportional.

Explanation:

At constant temperature and pressure the volume of a gas is directly proportional to the number of moles of gas. Also given a constant temperature and volume the pressure of a gas is directly proportional to the number of moles of gas.

This means that if V is constant then

P = n (RT/V) then n= PV/RT. As P is increased, T is also increased thereby decreasing the value of n since pressure and temperature are directly proportional.

6 0
2 years ago
25.0 mL of a hydrofluoric acid solution of unknown concentration is titrated with 0.200 M NaOH. After 20.0 mL of the base soluti
lesantik [10]

Answer:

[HF]₀ = 0.125M

Explanation:

NaOH + HF => NaF + H₂O

Adding 20ml of 0.200M NaOH into 25ml of HF solution neutralizes 0.004 mole of HF leaving 0.004 mole NaF in 0.045L with 0.001M H⁺ at pH = 3.   This is 0.089M NaF and 0.001M HF remaining.

=> 45ml of solution with pH = 3 and contains 0.089M NaF from titration becomes a common ion problem.

                HF  ⇄    H⁺    +      F⁻

C(eq)       [HF]     10⁻³M      0.089M (<= soln after adding 20ml 0.200M NaOH)

Ka = [H⁺][F⁻]/[HF]₀ => [HF]₀ = [H⁺][F⁻]/Ka

[HF]₀ = (0.001)(0.089)/(7.1 x 10⁻⁴) M = 0.125M

6 0
2 years ago
Other questions:
  • PLEASE HELP 100 POINTS!!!
    6·2 answers
  • What are the chemical properties of acids
    10·1 answer
  • How write 5601 in scientific notation
    7·1 answer
  • Which process is making the pots handle hot?
    11·2 answers
  • PLEASE HELP ME ASAP!!! THIS IS DUE UNTIL 1:30 PM!!! Tell how many Elements are in this compound and tell what the Elements are.
    13·2 answers
  • Zinc crystals is made from zinc Oxide and which acid ​
    7·2 answers
  • Using stoichiometry, you predict that you should be able to use 314.0 g of Al to produce 1551 g of AlCi3. In your lab
    8·1 answer
  • The following compound is used as an adhesive in the oil and gas industry.
    10·1 answer
  • What kind of answer is that? Definitely cancelling this service...be for real
    14·2 answers
  • Can you help give examples of elements, compounds, and mixtures? My friend is having trouble with it.
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!