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
melomori [17]
3 years ago
7

Which of the following substances are elements

Chemistry
2 answers:
Ugo [173]3 years ago
6 0
C. Protons, neutrons, electrons
mina [271]3 years ago
4 0

Answer:

I'm not much help but I think it is b

You might be interested in
A 115.0-g sample of oxygen was produced by heating 400.0 g of potassium chlorate.2KClO3 Right arrow. 2KCI + 3O2What is the perce
STALIN [3.7K]

Answer:

73.4% is the percent yield

Explanation:

2KClO₃ →  2KCl  + 3O₂

This is a decomposition reaction, where 2 moles of potassium chlorate decompose to 2 moles of potassium chloride and 3 moles of oxygen.

We determine the moles of salt: 400 g . 1. mol /122.5g= 3.26 moles of KClO₃

In the theoretical yield of the reaction we say:

2 moles of potassium chlorate can produce 3 moles of oxygen

Therefore, 3.26 moles of salt, may produce (3.26 . 3) /2 = 4.89 moles of O₂

The mass of produced oxygen is: 4.89 mol . 32 g /1mol = 156.6g

But, we have produced 115 g. Let's determine the percent yield of reaction

Percent yield = (Produced yield/Theoretical yield) . 100

(115g / 156.6g) . 100 = 73.4 %

5 0
3 years ago
Solid aluminum hydroxide reacts with a solution of hydrobromic acid. write a balanced molecular equation and a balanced net ioni
Stolb23 [73]
<span>To find the balanced molecular equation, we need to find the symbols for each element and their charges and then balanced the equation. This comes out to: Al(OH)3(aq) + 3HBR(aq) ---> AlBr3(aq) + 3H2O(l) The net ionic equation is adding the charges and separating them into basic components. Al3+ + 3OH- + 3H+ + 3BR- --> Al3+ + 3Br + H3O+ We can cancel out the aluminum and bromine to get: 3OH-(aq) + 3H+(aq) --> 3H2O(l)</span>
4 0
3 years ago
Read 2 more answers
Which cohesive forces are the strongest in water?
jeyben [28]

When cohesive force is stronger than the adhesive force: concave up meniscus, water forms droplets on surface

4 0
3 years ago
How does a catalyst work
blondinia [14]
It speeds up chemical reactions
3 0
3 years ago
Read 2 more answers
Hich of these reactions is a combustion reaction?
4vir4ik [10]
For combustion reaction we need oxygen and the results most of the time produce heat which mean first one is correct.
8 0
3 years ago
Read 2 more answers
Other questions:
  • A piece of iron (CsFe = 0.45 J/g·⁰C) with a mass of 4.45 g at temperature of 101.0 oC is dropped into an insulated calorimeter c
    5·1 answer
  • Please Help I need this to be done by today. There is a big reward if you get it right.
    12·1 answer
  • Is it true or false that dry air is 78% nitrogen and 21% carbon dioxide?
    6·1 answer
  • 30 POINTS! 7TH GRADE WORK! NO NONSENSE ANSWERS!
    12·1 answer
  • Help asap!!!!!!!!<br><br> How much net force is required to accelerate a 50.00 kg mass at 4.00 m/s??
    13·1 answer
  • Which of the possible compounds has a mass of 163 grams when
    15·1 answer
  • The graph describes how the solubilities of two salts
    8·1 answer
  • Which description accurately represents a water molecule
    10·1 answer
  • Dimensional analysis can only be used for time, distance, mass, speed, volume, and chemical quantities.
    12·1 answer
  • Predict which substance has greater molar entropy. Explain.(b) HNO₃(aq) or HNO₃(l)
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!