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
Vitek1552 [10]
3 years ago
6

To run a spectrophotometry experiment, begin by _______ the spectrophotometer and preparing the samples. Be sure to select the c

orrect ________, then run a measurement on the _______ solution. Follow up by running measurements on _______ solutions. Once data is collected, turn off the instrument, clean the area, and discard the samples.
1.
a) cleaning
b) warming up
c) unplugging
2.
a) wavelength
b) transmittance
c) absorbance
3.
a) blank
b) aqueous
c) sample
4.
a) blank
b) aqueous
c) sample
Chemistry
1 answer:
12345 [234]3 years ago
8 0

Answer:

b) warming up a) wavelength a) blank c) sample

Explanation:

<em>To run a spectrophotometry experiment, begin by </em><em>warming up</em><em> the spectrophotometer and preparing the samples.</em> It is important that the equipment is warmed up for at least 30 minutes before starting the measurements.

<em>Be sure to select the correct </em><em>wavelength</em><em>, then run a measurement on the </em><em>blank</em><em> solution.</em> The selected wavelength depends on the analyte of interest. The black solution contains the same matrix but it doesn´t contain the analyte.

<em>Follow up by running measurements on </em><em>sample</em><em> solutions. Once data is collected, turn off the instrument, clean the area, and discard the samples. </em>The samples are those of unknown concentration that we want to determine.

You might be interested in
PLZ HELP IM CONFUSED
Marina CMI [18]

Answer:

9.1 mol

Explanation:

The balanced chemical equation of the reaction is:

CO (g) + 2H2 (g) → CH3OH (l)

According to the above balanced equation, 2 moles of hydrogen gas (H2) are needed to produce 1 mole of methanol (CH3OH).

To convert 36.7 g of hydrogen gas to moles, we use the formula;

mole = mass/molar mass

Molar mass of H2 = 2.02g/mol

mole = 36.7/2.02

mole = 18.17mol

This means that if;

2 moles of H2 reacts to produce 1 mole of CH3OH

18.17mol of H2 will react to produce;

18.17 × 1 / 2

= 18.17/2

= 9.085

Approximately to 1 d.p = 9.1 mol of methanol (CH3OH).

6 0
3 years ago
During our phase changes lab, where did we place the thermometer?
IrinaK [193]

The thermometer must be <u>in contact with the ice/water only</u>

Explanation:

In this experiment in the lab, the aim is to measure the specific latent heat of fusion of water.

The specific latent heat of fusion of a substance is the amount of heat energy required to completely melt a certain amount of the substance, mathematically:

\lambda = \frac{Q}{m}

where

Q is the heat supplied to the substance

m is the mass of the substance

In this experiment, the aim is to measure the specific latent heat of fusion of water. In order to do that, a mix of ice/water is heated with a certain amount of heat Q, and then it is evaluated the amount of mass m that undergoes melting.

An important precaution that must be taken in this experiment is that the temperature of the water/ice mixture remains constant and equal to the melting point of ice (otherwise, part of the heat supplied to the mixture is used to increase the temperature of the water, resulting in an inaccurate measure of Q). Therefore, a thermometer must be used to check constantly the temperature, and this thermometer must be placed inside the ice/water mixture only (It should not touch the saucepan, whose temperature can be higher).

So, the correct answer is

in contact with the ice/water only

Learn more about specific heat:

brainly.com/question/3032746

brainly.com/question/4759369

#LearnwithBrainly

3 0
3 years ago
In acetyl CoA formation, the carbon-containing compound from glycolysis is oxidized to produce acetyl CoA. From the following co
kondor19780726 [428]

Answer:

- Net Input: NAD⁺, coenzyme A, pyruvate

- Net Output: NADH, acetyl CoA, CO₂

- Not input or output: O₂, ADP, glucose and ATP

Explanation:

Hello,

In this case, it is important to recall that acetyl-CoA is produced either by oxidative decarboxylation of pyruvate derived from glycolysis, which is carried out into the mitochondrial matrix, by cause of the oxidation of high-order fatty acids, or by oxidative degradation of very specific amino acids. Acetyl-CoA then enters in the citric acid cycle where it is oxidized in the light of energy production.

In this manner, during such processes, there are some net inputs and outputs, therefore, they are sorted as show below, considering there some of them not classified neither as input nor output:

- Net Input: NAD⁺, coenzyme A, pyruvate

- Net Output: NADH, acetyl CoA, CO₂

- Not input or output: O₂, ADP, glucose and ATP

Best regards.

8 0
3 years ago
The student wants to test the conductivity of each solution. Prior to carrying out the investigation, the student needs to ident
puteri [66]

Answer:b

Explanation: the particles will soon dissolve which means that the particles are changing but the volume is staying the same and the concentration is changing

3 0
2 years ago
Read 2 more answers
Competition for resources within an elk herd living in a national park can become severe. What
harkovskaia [24]
High popularity density
6 0
3 years ago
Other questions:
  • How many electrons would Potassium with a +2 charge have?
    9·1 answer
  • Energy transfer by convection is usually restricted to what type of substance?
    15·1 answer
  • Humans and other complex organisms have a hierarchical system of organization. Which of the following statements is true regardi
    14·1 answer
  • The standard cell potential, E°cell, for a reaction in which two electrons are transferred between the reactants is +1.33 V. Cal
    7·1 answer
  • What will the presence of H+ ions in a solution cause?
    8·2 answers
  • Chlorine has seven electrons in its valence shell. It accepts an electron to complete its octet and becomes a chlorine ion (Cl-)
    6·1 answer
  • How many liters of fat would have to be removed to result in a 5.2 lb weight loss? The density of human fat is 0.94 g/mL?​
    15·1 answer
  • Can someone pls help me with this its due in 20 minutes.
    12·1 answer
  • What is the pH of a solution of RbOH with a concentration of 0.86 M? Answer to 2 decimal places
    7·1 answer
  • Jon does an experiment in which he varies the amount of calcium chloride (CaCl2) powder used for the chemical reaction with sodi
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!