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
nexus9112 [7]
3 years ago
11

Pure substances include

Chemistry
1 answer:
eduard3 years ago
4 0
B. elements and compounds
You might be interested in
When two substances react to form products, the reactant which is used up is called the ____.
Maksim231197 [3]
The reactant being used up is called limiting reagent as it limits the total amount of product produced.

if 4 units of HCL gives 2 units of Cl therefore
4:2
0.98:x
x=(0.98*2) /4
x=0.49L
3 0
3 years ago
Hydrobromic acid, HBr, is a strong acid. Hydrofluoric acid, HF, is a weak acid. If you prepared equal
snow_tiger [21]
HBr and HF are both monoprotic Arrhenius acids—that is, in aqueous solution, they dissociate and ionize to give hydrogen ions. A strong acid ionizes completely; a weak acid ionizes partially.

In this case, HBr, being a strong acid, would ionize completely in water to yield H+ and Br- ions. However, HF, being a weak acid, would ionize only to a limited extent: some of the HF molecules will ionize into H+ and F- ions, but most of the HF will remain undissociated.

pH is, by definition, a measurement of the concentration of hydrogen ions in solution (pH = -log[H+]). A higher concentration of hydrogen ions gives a lower pH, while a lower concentration of hydrogen ions gives a higher pH. At 25 °C, a pH of 7 indicates a neutral solution; a pH less than 7 indicates an acidic solution; and a pH greater than 7 indicates a basic solution.

If we have equal concentrations of HBr and HF, then the HBr solution will have a greater concentration of hydrogen ions in solution than the HF solution. Consequently, the pH of the HBr solution will be less than the pH of the HF solution.

Choice A is incorrect: Strong acids like HBr dissociate completely, not partially.

Choice B is incorrect: While the initial concentration of HBr and HF are the same, the H+ concentration in the HBr solution is greater. Since pH is a function of H+ concentration, the pH of the two solutions cannot be the same.

Choice C is correct: A greater H+ concentration gives a lower pH value. The HBr solution has the greater H+ concentration. Thus, the pH of the HBr solution would be less than that of the HF solution.

Choice D is incorrect for the reason why choice C is correct.

4 0
3 years ago
Which of the following is a correct representation of the isotope of sulfur that has 19 neutrons? sulfur-19 sulfur-35 sulfur-16
Delicious77 [7]

Answer:

sulfur-35

Explanation:

Sulfur-35 is a radioactive isotope that contains 19 neutrons.

Isotopes are represented with mass numbers. Mass number is the addition of number of proton and number of neutrons.

The number of proton in sulfur = 16

Number of neutron = 19

So, mass number = no. of protons + no. of neutrons

                              = 16 + 19

                              = 35

Hence, the correct answer is sulfur-35.

4 0
3 years ago
Given these reactions, where X represents a generic metal or metalloid 1) H2(g)+12O2(g)⟶H2O(g)ΔH1=−241.8 kJ 1) H2(g)+12O2(g)⟶H2O
Bond [772]

Answer:

ΔH = -793,6 kJ

Explanation:

It is possible to obtain ΔH of this reaction using Hess's law that says you can sum the half-reactions ΔH to obtain the ΔH of the global reaction:

If half-reactions are:

1) H₂(g) + ¹/₂O₂(g) ⟶ H₂O(g) ΔH₁ = −241.8 kJ

2) X(s) + 2Cl₂(g) ⟶ XCl₄(s) ΔH₂ = +356.9 kJ  

3) ¹/₂H₂(g) + ¹/₂Cl₂(g) ⟶ HCl(g) ΔH₃ = −92.3 kJ

4) X(s) + O₂(g) ⟶ XO₂(s) ΔH₄ = −639.1 kJ

5) H₂O(g) ⟶ H₂O(l) ΔH₅ = −44.0 kJ

The sum of (4) + 4×(3) - (2) - 2×(1) - 2×(5) is:

(4) X(s) + O₂(g) ⟶ XO₂(s) ΔH = −639.1 kJ

+4×(3) 2H₂(g) + 2Cl₂(g) ⟶ 4HCl(g) ΔH = −369,2 kJ

-(2) XCl₄(s) ⟶ X(s) + 2Cl₂(g) ΔH = -356,9 kJ

-2×(1) 2H₂O(g) ⟶ 2H₂(g) + O₂(g) ΔH = +483,6 kJ

-2×(5) 2H₂O(l) ⟶ 2H₂O(g) ΔH = +88.0 kJ

= <em>XCl₄(s) + 2H₂O(l) ⟶ XO₂(s) + 4HCl(g)</em>

Where ΔH is:

ΔH = -639,1 kJ -369,2 kJ -356,9 kJ +483,6 kJ +88,0 kJ

<em>ΔH = -793,6 kJ</em>

I hope it helps!

5 0
3 years ago
An economical substitute for vitreous silica is a high-silica glass made by leaching the B2O3-rich phase from a two-phase borosi
stich3 [128]

Answer:48kg of SiO2, 0.5kg of Al2O3, and 1.5kg of B2O3

Will be the final product

Explanation:

I) 96wt% of SiO2 will amount to 96/100*50 = 0.96*50=48kg of SiO2

ii) 1wt% of Al2O3 will amount to 1/100*50 = 0.01*50=0.5kg of Al2O3

III) 3wt% of B2O3 will amount to 3/100*50 = 0.03*50=1.5kg of B2O3..

The overall product form 48+ 0.5+1.5= 50kg

7 0
3 years ago
Other questions:
  • WRITE INCOMPLETE COMBUSTION OF ETHANE
    7·1 answer
  • #1: In an icy glass of lemonade, which of the following is the solvent?
    14·1 answer
  • After your body breaks down food what are three things that can happen to the atoms from your food
    13·1 answer
  • Identify the products that are in equilibrium with NH3 and H2O.Identify the products that are in equilibrium with and .NH2−and H
    12·2 answers
  • When wood burns what 3 types of chemical energy is it?
    8·1 answer
  • When an atom forms chemical bonds, its_becomes more stable
    14·1 answer
  • Which of the following chemical formulas could represent a stable compound formed with an element "X" from group 1A and Oxygen?
    9·1 answer
  • Can someone answer 2 for me please?
    8·2 answers
  • Diffusion is the movement of solutes from an area of
    6·2 answers
  • Perform the following
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!