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
coldgirl [10]
3 years ago
15

For which of the following activities might you want to hire a chemist?

Chemistry
1 answer:
yarga [219]3 years ago
5 0

examining the structure of plant cells

You might be interested in
It is difficult to extinguish a fire on a crude oil tanker, because each liter of crude oil releases 2.80 × 10 7 J 2.80×107 J of
Alborosie

Answer:

The question is incorrect and incomplete. Here's the correct question:

It is difficult to extinguish a fire on a crude oil tanker, because each liter of crude oil releases 2.80 × 10 7 J  of energy when burned. To illustrate this difficulty,a) calculate the number of liters of water that must be expended to absorb the energy released by burning 1.00 L  of crude oil, if the water has its temperature raised from 23.5 °C to 100 °C , it boils, and the resulting steam is raised to 315 °C. b)Discuss additional complications caused by the fact that crude oil has less density than water.

Explanation:

Q= mc ΔT

Q= heat energy

m is mass

ΔT is change in temperature and c is specific heat capacity

calculating heat for latent heat of vaporisation

Q= ml where l is latent heat of vaporisation

a) Total heat energy used= heat required to raise temperature from 23.5 °C to 100 °C, heat required to boil water and heat required to further raise temperature from 100 °C to 315°C

Q = mc ΔT₁ + mL + mc ΔT₂

Q = m(c ΔT₁ + L + c ΔT₂)

m= Q÷(c ΔT₁ + L + c ΔT₂)

Q= 2.8 X 10⁷ J

c=4186J/kg°C

L=2256 x 10³J/kg

ΔT₁=76.5°C(100°C-23.5°C)

ΔT₂= 215°C(315°C-100°C)

(c ΔT₁ + L + c ΔT₂)= 4186J/kg°C *76.5°C + 2256 x 10³J/kg + 4186J/kg°C*215°C =3476219J/Kg

m= 2.8 x 10⁷J ÷3476219J/Kg

m =80.54 Kg

volume = mass÷ density

=80.54kg ÷ 10³kg/m³( density of water)

=0.0854m³

0.001m³ = 1 lL0.08054m³= 0.08054m³ /0.001m³= 80.54L

VOLUME is 80.54litres

b) since the density of crude is less than the density of water,and 80L of additional water is added, it'll make the crude to float on water thus inhibiting the extinguishing process

4 0
3 years ago
How many of the following are oxidation-reduction reactions? I. reaction of a metal with a nonmetal II. synthesis III. combustio
nadezda [96]

Answer : The oxidation-reduction reactions are:

I. reaction of a metal with a nonmetal

II. synthesis

III. combustion

Explanation :

Redox reaction or Oxidation-reduction reaction : It is defined as the reaction in which the oxidation and reduction reaction takes place simultaneously.

Oxidation reaction : It is defined as the reaction in which a substance looses its electrons. In this, oxidation state of an element increases. Or we can say that in oxidation, the loss of electrons takes place.

Reduction reaction : It is defined as the reaction in which a substance gains electrons. In this, oxidation state of an element decreases. Or we can say that in reduction, the gain of electrons takes place.

I. Reaction of a metal with a nonmetal :

When sodium react with chlorine gas then it react to give sodium chloride.

2Na+Cl_2\rightarrow 2NaCl

In this reaction, the oxidation state of sodium changes from (0) to (+1) and shows oxidation and the oxidation state of chlorine changes from (0) to (-1) and shows reduction. So, It is an oxidation-reduction reaction.

II. Synthesis reaction :

A chemical reaction where multiple substances or reactants combine to form a single product.

When hydrogen react with oxygen then it react to give water.

2H_2+O_2\rightarrow 2H_2O

In this reaction, the oxidation state of hydrogen changes from (0) to (+1) and shows oxidation and the oxidation state of oxygen changes from (0) to (-2) and shows reduction. So, It is an oxidation-reduction reaction.

III. Combustion reaction :

A chemical reaction in which a hydrocarbon reaction with the oxygen to give product as carbon dioxide and water.

When methane react with oxygen gas then it react to give carbon dioxide and water.

CH_4+2O_2\rightarrow CO_2+2H_2O

In this reaction, the carbon of methane gain oxygen and shows oxidation and the oxygen gas gain hydrogen and shows reduction. So, It is an oxidation-reduction reaction.

IV. Precipitation reaction :

It is defined as the reaction in which an insoluble salt formed when two aqueous solutions are combined.

The insoluble salt that settle down in the solution is known an precipitate.

It is a double displacement reaction. So, it is not an oxidation-reduction reaction.

V. Decomposition reaction :

A chemical reaction in which the the larger molecule decomposes to give two or more smaller molecules.

The oxidation state remains same on reactant and product side. So, it is not an oxidation-reduction reaction.

3 0
3 years ago
In a study of the conversion of methane to other fuels, a chemical engineer mixes gaseous methane and gaseous water in a 0.778 L
sergejj [24]

Answer:

the water concentration at equilibrium is

⇒ [ H2O(g) ] = 0.0510 mol/L

Explanation:

  • CH4(g) + H2O(g) ↔ CO(g) + 3H2(g)

∴ Kc = ( [ CO(g) ] * [ H2 ]³ ) / ( [ CH4(g) ] * [ H2O(g) ] ) = 0,30

  • equilibrium:

⇒ [ CO(g) ] = 0.206 mol / 0.778 L = 0.2648 mol/L

⇒ [ H2(g) ] = 0.187 mol / 0.778 L = 0.2404 mol/L

⇒ [ CH4(g) ] = 0.187 mol / 0.778 L = 0.2404 mol/L

replacing in Kc:

⇒ ((0.2648) * (0.2404)³) / ([ H2O(g) ] * 0.2404 ) = 0.30

⇒ 0.0721 [ H2O(g) ] = 3.679 E-3

⇒ [ H2O(g) ] = 0.0510 mol/L

7 0
3 years ago
1. An oxide of chromium is found to have the following % composition: 68.4% Cr
abruzzese [7]

Answer:

Empirical formula is Cr₂O₃.

Explanation:

Given data:

Percentage of Cr = 68.4%

Percentage of O = 31.6%

Empirical formula = ?

Solution:

Number of gram atoms of Cr = 68.4 / 52 = 1.3 2

Number of gram atoms of O = 31.6 / 16 = 1.98

Atomic ratio:

                            Cr               :         O

                           1.32/1.32     :       1.98/1.32

                               1              :        1.5

Cr : O = 1 :  1.5

Cr : O = 2(1 : 1.5)

Empirical formula is Cr₂O₃.

6 0
3 years ago
What is The Magnus Effect/Force? Explain.
cluponka [151]

Answer:

dk

Explanation:

6 0
3 years ago
Other questions:
  • 26.2 g piece of copper metal is heated from 21.5°C to 201.6°C. Calculate the amount of heat absorbed by the metal. The specific
    15·1 answer
  • When given any reaction how do I figure out the products and then balance it?
    8·1 answer
  • The half-reaction occurring at the anode in the balanced reaction shown below is ________. 3mno4- (aq) + 24h+ (aq) + 5fe (s) → 3
    10·1 answer
  • The normal boiling point for acetone is 56.5°c. at an elevation of 5300 ft the atmospheric pressure is 630. torr. what would be
    11·1 answer
  • Which planet is sometimes called Uranus’s twin? Saturn Pluto Jupiter Neptune
    10·2 answers
  • If a gas occupies 22.4 L at 0.265 atm, then what will the pressure be in atmospheres if the gas occupies 35.52 L? Assume all oth
    11·1 answer
  • What are the characteristics found in transition elements ?​
    10·2 answers
  • Can anyone please help?
    10·1 answer
  • Your friend looks at a piece of ice and says “Solids, like ice, have a fixed shape because the particles are not moving.” Is you
    11·2 answers
  • Fusion is safer than fussion because....
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!