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
kodGreya [7K]
3 years ago
11

Which step accurately describes how to measure the final burette volume?

Chemistry
2 answers:
8090 [49]3 years ago
4 0
To accurately measure the final volume of a solution in a burette, it is important that you read of the measurement in the lower meniscus like for water and for substances like mercury you read it on the upper meniscus. This is the standard way of reading volumes in laboratory apparatus. Also, it should be that the apparatus standing vertically in a plain surface.
LekaFEV [45]3 years ago
3 0

Answer:

The precision to measure a volume in a burette will depend on the shape of the meniscus that forms the liquid. In the case of a concave meniscus, its reading will be made at the lowest height of the liquid surface. This point should touch the upper edge in the division of the burette scale. In the case of a convex meniscus, its reading will be made at the highest height of the liquid surface. This point should touch the bottom edge in the burette scale division.

Explanation:

The accuracy when reading the correct volume in a burette depends on the type of meniscus. If the molecules of a liquid have a greater attraction to the glass wall, the meniscus will have a concave shape, for example, aqueous solutions. A requirement to measure exactly is the adjustment of the meniscus. As stated before, if the meniscus shape is concave, the volume will be read at the lowest height of the liquid surface. If the meniscus is convex, the volume will be taken at the highest height of the liquid surface. Convex menisci are formed by substances such as mercury.

You might be interested in
A 0.652-g sample of a pure strontium halide reacts with excess sulfuric acid. the solid strontium sulfate formed is separated, d
seraphim [82]

Answer:

The formula of the original halide is SrCl₂.

Explanation:

  • The balanced equation of this reaction is:

SrX₂ + H₂SO₄ → SrSO₄ + 2 HX, where X is the halide.

  • From the equation stichiometry, 1.0 mole of strontium halide will result in 1.0 mole of SrSO₄.
  • The number of moles of SrSO₄ <em>(n = mass/molar mass) </em>= (0.755 g) / (183.68 g/mole) = 4.11 x 10⁻³ mole.
  • The number of moles of SrX are  4.11 x 10⁻³ moles from the stichiometry of the balanced equation.
  • n = mass / molar mass, n =  4.11 x 10⁻³ moles and mass = 0.652 g.
  • The molar mass of SrX₂ = mass / n = (0.652) / (4.11 x 10⁻³ moles) = 158.62 g/mole.
  • The molar mass of SrX₂ (158.62 g/mole) = Atomic mass of Sr (87.62 g/mole) + (2 x Atomic mass of halide X).
  • The atomic mass of halide X = (158.62 g/mole) - (87.62 g/mole) / 2 = 71 / 2  g/mole = 35.5 g/mole.
  • This is the atomic mass of Cl.
  • <em>So, the formula of the original halide is SrCl₂</em>.
4 0
3 years ago
The chemical equation below shows the formation of aluminum oxide (Al2O3) from aluminum (Al) and oxygen (O2).
Rufina [12.5K]

Answer:

Mass = 182.4 g

Explanation:

Given data:

Number of moles of Al₂O₃ = 3.80 mol

Mass of oxygen required = ?

Solution:

Chemical equation:

4Al + 3O₂    →       2Al₂O₃

Now we will compare the moles of aluminum oxide and oxygen.

                Al₂O₃           :           O₂

                   2               :            3

                 3.80            :         3/2×3.80 = 5.7

Mass of oxygen:

Mass = number of moles × molar mass

Mass = 5.7 mol × 32 g/mol

Mass = 182.4 g

4 0
2 years ago
Draw the major organic product(s) for the reaction. The starting material is a benzene ring with one substituent. The substituen
Mice21 [21]

Answer:

See Explanation

Explanation:

In electrophilic aromatic substitution, the benzene ring undergoes substitution when it is reacted with suitable electrophiles.

The products of electrophilic aromatic substitution depends on the substituents already present on the benzene ring. Some substituents activate the ring towards electrophilic substitution and direct the incoming electrophile to the ortho and para positions on the ring while some substituents deactivate the benzene ring towards electrophilic substitution and direct the incoming electrophlle to the meta position on the ring.

The amide substituent is moderately activating and is an ortho, para director hence the products shown in the mage attached to this answer.

3 0
3 years ago
"A base is a substance that produce OH-ions." Which definition of a base is this?
Andru [333]

Answer:

C. Arrhenius

An Arrhenius base is a substance that dissociates in water to form hydroxide (OH–) ions. In other words, a base increases the concentration of OH– ions in an aqueous solution.

Explanation:

pls mark as brainliest

3 0
2 years ago
A reasonable pka for a weak base is:<br><br> 10.3<br><br> 0.9<br><br> 5.8<br><br> 7.4<br><br> 13.1
andriy [413]

Answer:

0.9

Explanation:

The pka represents the force by which the molecules need to dissociate for the acids ,

Hence , lower the pka stronger will be the acid and that therefore will  dissociate completely and vice versa , for a weak acid higher the pka .

And in case of a base , it will be completely reversed , lower pKa , weaker base ,

and higher pKa , stronger base .

From the data of the question ,

0.9 is the lowest value of the pKa , hence , weakest base .

7 0
3 years ago
Other questions:
  • PLEASE HELP ME QUICKLY!!!!!
    8·2 answers
  • Which of the following is a property of both gases and liquids?
    6·1 answer
  • The pyruvic acid from glycolysis can be converted to acetic acid, which can enter the citric acid cycle. Because this process is
    5·1 answer
  • How much ice at 0°C could be melted by the addition of 15 kJ of heat? (ΔHfus = 6.01 kJ/mol)
    13·2 answers
  • Which of the following advances in food production were attributed to the Green Revolution of the 1960s and 1970s
    6·2 answers
  • A balloon contains 0.5 L of air at 101.5 kPa. You squeeze it to a volume of 0.25 L. What is the pressure of air inside the ballo
    6·1 answer
  • The difference between GDP and GNP
    13·1 answer
  • What is the meaning of flourish?
    15·1 answer
  • Determine if the compound is molecular or ionic: SiCI2
    7·1 answer
  • In the equation below
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!