1 When chemicals pour on the skin, the laboratory first aid is to ---------------.
Apply 1% sodium carbonate
Apply 1% boric acid solution
Flush the eye with a copious amount of clean lukewarm running water
Wash with soap and warm water
2 For cut sustained in the laboratory which involve serious bleeding , the bleeding can be checked by --------------.
Applying direct pressure with a clean, sterile dressing
Elevate the wound above the heart and apply direct pressure with a clean, sterile dressing
Apply 1% sodium carbonate
Apply 1% boric acid solution
3 All these are pain relieving cream applied to burns and scalds where the skin is not broken in the laboratory EXCEPT -------------.
Jelly
Acriflavine
Shea butter
Moisturising cream
4 The second action to perform to resucitate a victim of gas inhaltion in the laboratory is to ----------------.
Remove the victim from danger area
Apply artificial respiration
Loosen clothing
Immediately seek emergency medical assistance
5 The first aid given to a person that ingested poisonous chemical in the laboratory include all these EXCEPT ----------------.
cold water to drink
Cold milk to drink
inducing vomiting
seek emergency medical assistance
6 The SI designation for amount of mole is --------------.
mole
mass
metre
candela
7 The SI designation candela is for --------------base unit.
Electric current
Luminous intensity
Amount of substance
Temperature
8 One of the following is not a proper way of preparing 0.025M solution from 1.00M stock solution.
2.5 mL of stock solution is diluted to 100mL
25 mL of stock solution is made up to 1000mL
12.5 mL of the stock solution is made up to 500mL
12.5 mL of the stock solution is made up to 750mL
9 All the following apparatus are needed for the preparation of a solution of hydrochloric acid, HCl, from the concentrated solution EXCEPT --------------.
Measuring cylinder
Burette
Crucible
Volumetric flask
10 If
15cm 3
of 10.25M HCl solution is made up to volume in a 500 Ml volumetric flask, what will be its new concentration?
0.306M
3.06M
5.13M
0.52M
11 In the preparation of a solution, it is advisable to shake the mixture well. This is necessary to ----------------.
Ensure that the solution precipitates out very well
Induce air bubbles in the solution
Produce a homogenous solution
Facilitate use of lesser volume of water
12 To dilute an acid with water, acids are added to water and not water to acid because -----------------.
Acids are more vicourse than water
Water is weaker than acid
Dissolution of acid in water is exothermic which could be explosive
Acids will not dissolve in water if done wrongly
13 During standardization of HCl with sodium carbonate titration, the pipette is rinsed with distilled water and thereafter with ------------.
the HCl solutin
The methyl orange indicator
the
Na 2 CO 3
solution
More water
14 In a standardization titration involving hydrochloric acid and sodium carbonate, a student recoirded the following results for the volume of hydrochloric acid used against 10.00mL of the sodium carbonate solution : 15.60; 14.50; 14.70 aqnd 14.20. What is
14.60mL
14.75mL
14.47mL
14.00mL
15 In a standardization titration involving hydrochloric acid and sodium carbonate, a student recoirded the following results for the volume of hydrochloric acid used against 10.00mL of the sodium carbonate solution : 15.60; 14.50; 14.70 aqnd 14.20. If the c
1.02 Ml
1.03mL
1.07mL
1.04M
16 All these are safety precautions in a chemistry laboratory EXCEPT -----------.
carefully read all labels before using chemicals
perform only experiments that have been authorized by the instructor
wear loose clothings when in the chemistry laboratory
never pour water into concentrated acid.
17 Do not use flat-bottomed flasks in in vacuum experiment is a ------------- hazard
Explosion
Fire
Chemical
General safety
18 When an acidic chemical splashes into the eyes, the first thing to do is ---------
Apply 1% sodium carbonate
Apply 1% boric acid solution
Flush the eye with a copious amount of clean lukewarm running water
Put eye drop
19 When an acidic chemical splashes into the eyes, the second action to be carried out is ---------.
Apply 1% sodium carbonate
Apply 1% boric acid solution
Flush the eye with a copious amount of clean lukewarm running water
Put eye drop
20 When an alkalis chemical splashes into the eye, the second action to be carried out is ---------------.
Apply 1% sodium carbonate
Apply 1% boric acid solution
Flush the eye with a copious amount of clean lukewarm running water
Put eye drop
See your other posts. These make 60.
ppls help wit all d answers pls
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d,a,b,a,b,a,b,d,c,a,c,a,c,b,c,c,d,a,b,b
Flush the eye with a copious amount of clean lukewarm runing water
applying direct pressuer with a clean sterile dressing
1. When chemicals pour on the skin, the laboratory first aid is to flush the affected area with a copious amount of clean lukewarm running water. This helps to immediately remove the chemical from the skin and dilute it, reducing further damage.
2. For a cut sustained in the laboratory with serious bleeding, the bleeding can be stopped by applying direct pressure with a clean, sterile dressing. This helps to compress the blood vessels and reduce bleeding. If the bleeding is severe, elevating the wound above the heart while applying pressure can also be effective.
3. Pain-relieving creams applied to burns and scalds where the skin is not broken in the laboratory include jelly, shea butter, and moisturizing cream. Acriflavine is not typically used as a pain reliever for burns and scalds.
4. The second action to perform to resuscitate a victim of gas inhalation in the laboratory is to apply artificial respiration. This helps to provide oxygen to the victim and stimulate breathing. The first action is to remove the victim from the danger area.
5. The first aid given to a person that ingested a poisonous chemical in the laboratory includes seeking emergency medical assistance and not inducing vomiting. Cold water or cold milk is not recommended as it can potentially worsen the situation. It is important to seek professional medical help immediately.
6. The SI designation for the amount of mole is "mole." The mole is the SI unit for measuring the amount of a substance.
7. The SI designation "candela" is for the base unit of luminous intensity. It is used to measure the brightness or intensity of light.
8. The proper way of preparing a 0.025M solution from a 1.00M stock solution is by diluting 12.5 mL of the stock solution to 500 mL, and not to 750 mL or 100 mL.
9. The apparatus needed for the preparation of a solution of hydrochloric acid, HCl, from the concentrated solution typically includes a measuring cylinder, burette, and volumetric flask. A crucible is not necessary for this process.
10. If 15 cm3 of 10.25M HCl solution is made up to volume in a 500 mL volumetric flask, the new concentration will be 0.306M. This can be calculated using the dilution formula: C1V1 = C2V2, where C1 is the initial concentration, V1 is the initial volume, C2 is the final concentration, and V2 is the final volume.
11. Shaking the mixture well during the preparation of a solution is necessary to produce a homogeneous solution. This means that the solute (substance being dissolved) is evenly distributed throughout the solvent (the substance doing the dissolving).
12. Acids should be added to water when diluting them because the dissolution of acids in water is exothermic, meaning it releases heat. Adding water to concentrated acid can cause a rapid release of heat, potentially leading to a dangerous situation or an explosion. Adding acid to water allows for better control of the mixing process.
13. During standardization of HCl with sodium carbonate titration, the pipette should be rinsed with distilled water and then with the Na2CO3 solution. This ensures that there are no residues or contaminants from previous solutions in the pipette that could affect the accuracy of the titration.
14. In a standardization titration involving hydrochloric acid and sodium carbonate, the average volume of hydrochloric acid used against 10.00 mL of the sodium carbonate solution is 14.60 mL. This is calculated by taking the average of the recorded volumes (15.60, 14.50, 14.70, and 14.20).
15. In a standardization titration involving hydrochloric acid and sodium carbonate, if the average volume of hydrochloric acid used against 10.00 mL of the sodium carbonate solution is 14.60 mL, the concentration of the HCl is 1.02M. This can be calculated using the equation: M1V1 = M2V2, where M1 is the concentration of the HCl, V1 is the volume used, M2 is the concentration of the Na2CO3, and V2 is the volume of Na2CO3 used.
16. All of the provided options are safety precautions in a chemistry laboratory, except for wearing loose clothing. It is important to wear appropriate clothing, such as a lab coat, that fits well and covers the body to protect against chemical spills and exposure.
17. The statement "Do not use flat-bottomed flasks in a vacuum experiment" is a general safety hazard. Using flat-bottomed flasks in vacuum experiments can cause implosions or glassware breakage due to the pressure difference inside and outside the flask.
18. When an acidic chemical splashes into the eyes, the first thing to do is to flush the eye with a copious amount of clean lukewarm running water. This helps to immediately remove the chemical from the eyes and dilute it, reducing further damage.
19. When an acidic chemical splashes into the eyes, the second action to be carried out is to seek medical assistance. It is crucial to consult a medical professional to ensure proper treatment and to minimize any potential damage caused by the chemical.
20. When an alkali chemical splashes into the eyes, the second action to be carried out is to flush the eye with a copious amount of clean lukewarm running water. This helps to immediately remove the chemical from the eyes and dilute it, reducing further damage.