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
Nitella [24]
2 years ago
6

Câu 15: Nguyên tử X nặng gấp 2 lần nguyên tử cacbon. Nguyên tử X đó có nguyên tử khối và

Chemistry
1 answer:
vlabodo [156]2 years ago
7 0

Answer:

A

Explanation:

You might be interested in
_____ are isotopes that emit radiation because they have unstable nuclei.
alexandr1967 [171]
The correct answer among the choices given is option B. Radioisotopes are isotopes that emit radiation because they have unstable nuclei. These are radioactive isotopes of an element. They are defined as atoms that contain an unstable combination of neutrons and protons.
7 0
3 years ago
Read 2 more answers
Which one of the following metallic element is liquid are room temperature​
cricket20 [7]

Answer:

The only liquid elements that can melt at standard temperature and pressure are bromine (Br) and mercury (Hg).

7 0
3 years ago
Calculate the pH for each of the following cases in the titration of 25.0 mL of 0.150 M sodium hydroxide with 0.150 M HBr(aq). (
Taya2010 [7]

Answer:

a) pH = 13.176

b) pH = 13

c) pH = 12.574

d) pH = 7.0

e) pH = 1.46

f) pH = 1.21

Explanation:

HBr + NaOH ↔ NaBr + H2O

∴ equivalent point:

⇒ mol acid = mol base

⇒ (Va)*(0.150mol/L) = (0.025L)*(0.150mol/L)

⇒ Va = 0.025 L

a) before addition acid:

  • NaOH → Na+  + OH-

⇒ <em>C </em>NaOH = 0.150 M

⇒ [ OH- ] = 0.150 M

⇒ pOH = - Log ( 0.150 )

⇒ pOH = 0.824

⇒ pH = 14 - pOH

⇒ pH = 13.176

b) after addition 5mL HBr:

⇒ <em>C </em>NaOH = (( 0.025)*(0.150) - (0.005)*(0.150)) / (0.025 + 0.005) = 0.1 M

⇒ <em>C </em>HBr = (0.005)*(0.150) / ( 0.03 ) = 0.025 M

⇒ [ OH- ] = 0.1 M

⇒ pOH = 1

⇒ pH = 13

c) after addition 15mL HBr:

⇒ <em>C </em>NaOH = ((0.025)*(0.150) - (0.015)*(0.150 ))/(0.04) = 0.0375 M

⇒ <em>C </em>HBr = ((0.015)*(0.150))/(0.04) = 0.0563 M

⇒ [ OH- ] = 0.0375 M

⇒ pOH = 1.426

⇒ pH = 12.574

d) after addition 25mL HBr:

equivalent point:

⇒ [ OH- ] = [ H3O+ ]

⇒ Kw = 1 E-14 = [ H3O+ ] * [ OH- ] = [ H3O+ ]²

⇒ [ H3O+ ] = 1 E-7

⇒ pH = 7.0

d) after addition 40mL HBr:

⇒ <em>C</em> HBr = ((0.04)*(0.150) - (0.025)*(0.150)) / (0.04 + 0.025) = 0.035 M

⇒ [ H3O+ ] = 0.035 M

⇒ pH = 1.46

d) after addition 60mL HBr:

⇒ <em>C</em> HBr = ((0.06)*(0.150) - (0.025)*(0.150)) / (0.06+0.025) = 0.062 M

⇒ [ H3O+ ] = 0.062 M

⇒ pH = 1.21

8 0
3 years ago
Read 2 more answers
Based on patterns in the periodic table, which list shows the acids in order from strongest to weakest?
GenaCL600 [577]

Answer:

Sorry I dont know this question

You can ask me computer related question.

sorry

Explanation:

Sorry

5 0
2 years ago
Read 2 more answers
What is an egg in a frying pan considered <br><br> Conduction <br> Convection <br> Radiation
viktelen [127]

Answer:

conduction

Explanation:

conduction is heat transfer by direct like frying an egg.

4 0
3 years ago
Read 2 more answers
Other questions:
  • A _________________ is developed through the scientific method, and it can be modified or improved upon. It may be represented b
    10·2 answers
  • Question 4 (1 point)<br> If you have exactly one million atoms how many moles do you have?
    8·1 answer
  • What kind of chemical bond is found between paired bases of the dna double helix?
    12·1 answer
  • Ms. Block's students are studying chemical reactions as well as the law of conservation of matter. A classic reaction occurs whe
    10·2 answers
  • 10. Which best describes the purpose of food?
    5·1 answer
  • A brick measures 0.018 dam by 6.5 cm by 17.3 cm. What is the volume of the brick in cubic centimeters
    6·1 answer
  • The force that keeps the planets in orbit is________.
    6·1 answer
  • Mr. Jones's prescription calls for 1.04 tablets per day. Based on this information, how many tablets should Mr. Jones take per d
    8·1 answer
  • What is the [Na2SO4] (MM = 142.04 g/mol) in ppt if 100.00 mL of a
    12·1 answer
  • 1. Have scientists been able to invent a perpetual motion machine?<br> O Yes<br> O No
    6·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!