What is the best safety practice recommended before leaving the chemistry laboratory?

Answers

Answer 1
Answer:

Answer:

Washing your hands properly.


Related Questions

In the following reaction 2C6H6 + 15O2 12CO2 + 6H2O how many grams of oxygen will react with 10.47 grams of benzene (C6H6)?
Which subatomic particle will be attracted by a positively charged object?(1) proton (3) electron(2) neutron (4) positron
You take an ice cube (mass = 18g) from the freezer (T=-10°C) and place it on the table. Later that day, you notice a puddle of water on the table that has reached ambient room temperature (20°C). How much heat must have been absorbed to make this happen? A) 1867.0 J B) 2260.4 J C) 7897.0 J D) 42657.0 J
An excellent tool to gauge the reliability of any theory is its capacity to generate correct? a.models b.predictions c.data d.hypotheses.
Ammonium hydroxide ionizes as follows: NH4OH(s) NH4 +(aq) + OH-(aq). If an excess of ammonium salt, such as NH4Cl (which ionizes to give NH4 +(aq) ions) is added to the equilibrium shown above, you could predict that the result will be to....

2. A sample of iron has the dimensions of 2.0 cm x 3.0 cm x2.0 cm. It has a mass of 94.0 grams. What is the density of
iron? (8 points)

Answers

Answer:

first change cm to m and g to kg so you will find the volume first which is 0.02 by 0.03 by 0.02 your answer is 0.000012 m . using the formula density=mass/volume take 0.094/ 0.00012 then divide

What is the percent composition by mass of nitrogen in NH4NO3 (gram-formula mass = 80.0 grams/mole)?(1) 17.5% (3) 52.5%
(2) 35.0% (4) 60.0%

Answers

Answer:

The correct option is (2) 35.0%

Explanation:

If we want to calculate the percent composition by mass of nitrogen in NH4NO3 we first need to calculate the mass of nitrogen in one mole of NH4NO3.

Because of the molecular form of NH4NO3 (it has 2 ''N'') we know that one mole of NH4NO3 contains 2 moles of N.

The molar mass of N (nitrogen) is 14.0067(g)/(mole)

This means that 1 mole of N contains 14.0067 grams of N.

Because we have 2 moles of N ⇒ (2moles).(14.0067(g)/(mole))=28.0134g

We know that in 1 mole of NH4NO3 we have 2 moles of N(28.0134 g of N).

To calculate the percent composition by mass of nitrogen we need to divide the mass of nitrogen in one mole of NH4NO3 by the mass of one mole of NH4NO3 and then multiply it by 100.

We know that in 1 mole of NH4NO3 there are 80.0 g of NH4NO3 (Because of the molar mass data) ⇒

((28.0134g)/(80.0g)).100=35.016 % ≅ 35.0%

We find that the percent composition by mass of nitrogen in NH4NO3 is 35.0%

We conclude that the correct option is (2) 35.0%

gram-formula=80.0grams/mole will be 35.0%

All parts of the rock cycle are connected, whether directly or indirectly. Which statementbest shows how sedimentary rocks are related to igneous rocks?
1.Under pressure, sedimentary rocks form from igneous rock.
2.Igneous rocks can weather, creating sediments that form sedimentary rocks.
3. During weathering, sedimentary rocks melt and form igneous rock.
4.Under pressure, igneous rock undergoes changes that form sedimentary rock.

Answers

Answer:

2. Igneous rocks can weather, creating sediments that form sedimentary rocks

Explanation:

Sedimentary rocks are formed from Igneous rocks when rocks are broken down by weathering.

What is the type of bond holding hydrogen and oxygen atoms together in a single h2o molecule? What is the type of bond holding hydrogen and oxygen atoms together in a single h2o molecule? Ionic bond covalent bond hydrogen bond?

Answers

it is a hydrogen bond

Answer:

It is a hydrogen bond.

Consider the following equilibrium:4KO2(s) + 2H2O(g) 4KOH(s) + 3O2(g)

Which of the following is a correct equilibrium expression?

A.
`"K"_("eq") = (["KOH"]^4["O"_2]^3)/(["KO"_2]^4["H"_2"O"]^2)`

B.
`"K"_("eq") = (["H"_2"O"]^2)/(["O"_2]^3)`

C.
`"K"_("eq") = (["KO"_2]^4["H"_2"O"]^2)/(["KOH"]^4["O"_2]^3)`

D.
`"K"_("eq") = (["O"_2]^3)/(["H"_2"O"]^2)`

Answers

Answer:

Answer is option D

Explanation:

The explanation is embedded in the word document attached

Answer:

Keq= [KOH]^4 [O2]^3/[[KO2]^4

Explanation:

4KO2(s) + 2H2O(l) → 4KOH(s) + 3O2(g)

Looking at the equation, the correct equilibrium expression is shown in the answer. The equilibrium constant for a reaction is given by the active masses of species involved in the reaction. The relative molar coefficients of species are raised to the power of their molar concentrations to give the active mass of each specie. This active mass now goes into the equilibrium equation.

Water is not included in the equilibrium equation because, as a solvent, it is present in large excess.

Which identifies an oxidation-reduction reaction?a double replacement reaction
a neutralization reaction
a reaction in which oxidation numbers change
a reaction in which no electrons are transferred.

Answers

Answer:

A reaction where oxidation numbers change.

A reduction is when electrons are gained while oxidation is when electrons are lost.