DMLT HSBTE Basic Chemistry Question Paper Examination July 2023 with Answer Solutions.

                 1st Sem. / DMLT Subject: Basic Chemistry 221912

Note: Multiple choice questions. All questions are compulsory (6x1=6)

Section A

• Q.1 pH value of pure water is

  • a) 5      b) 7

  • c) 6      d) 8      Ans (b) 7

• Q.2 When proteins are broken down_______are formed

  • a) Ozone           b) Molecules

  • c) Amino acids d) Current     Ans (C) Amino Acids

• Q.3 pH means

  • a) Potential of hydrogen       b) Presence of hydrogen

  • c) Presence of hemoglobin   d) Power of hemoglobin.    Ans: a) Potential of hydrogen

• Q.4 The most abundant element in the universe is

  • a) Hydrogen            b) Oxygen

  • c) Carbon dioxide   d) Silicon       Ans (A) Hydrogen.

• Q.5 Substances which increase the reaction rate is

  • a) Metal           b) Catalyst

  • c) Enzymes      d) Alloy        Ans (B) Catalyst

• Q.6 RBC stands for

  • a) Red Blood Cells         b) Blood Cells

  • c) White Blood Cells     d) Random Blood Cells.   Ans (A) Red Blood Cells

SECTION-B

Note: Objective/ Completion type questions. All questions are compulsory. (6x1=6)

• Q.7 What is meant by organic compounds?

Ans: Organic Compounds are chemical compounds that contain carbon atoms covalently bonded to other elements, usually hydrogen, oxygen, or nitrogen.Examples Carbohydrates, Proteins, urea, nucleic acids, etc.

• Q.8 What is vacutainer.

Ans: Vacutainer is a sterile glass or plastic tube with a rubber stopper that creates a vacuum seal. It is used to draw blood or fluid.

• Q.9 Define the Solution.

Ans: A solution is a homogeneous mixture of two or more substances. It consists of solute and solvent. The particle size of solute in solution is less than 1 nanometer.

• Q.10 What is photometry?

Ans: Photometry is the science of measuring a light beam based on its brightness that appears to the human eye.

• Q.11 Define Viscosity.

Ans: Viscosity is the resistance of a fluid to flow or deform.

• Q.12 Give two examples of inorganic compounds.

Ans: Water and Sulfuric acid.

SECTION-C

Note: Short answer type questions. Attempt any eight questions out of ten questions. (8x4=32)

• Q.13 Write a short note on Osmosis.

Ans: Osmosis is the movement of solvent molecules across a semipermeable membrane from an area of lower solute concentration to an area of higher solute concentration until equilibrium is established. A semipermeable membrane stops the movement of solutes.

Osmosis plays an important role in biological systems. It helps to maintain water balance inside the human body. Water balance ensures the proper functioning of cells. Examples: In the kidney, it helps reabsorption of water and certain solutes. The pressure developed by the movement of water molecules across the semipermeable membrane during osmosis is called osmotic pressure.

Factors affecting osmosis

• 1. Solute concentration: The greater the concentration difference, the faster will be the rate of osmosis.

• 2. Temperature: Rate osmosis increases with an increase in temperature

• 3. Pressure: Applying external pressure can reverse the osmosis.

• Q.14 Write a short note on blood collection.

Ans: Blood collection is carried out to assess various physiological parameters and to diagnose health conditions. The procedure should be performed by trained healthcare professionals to ensure accuracy and minimize the risk of contamination. The following steps are followed in blood collection for biochemical analysis.

• 1. Preparation: Ensure availability of all necessary equipment and supplies for blood collection such as sterile needle, vacutainer tube, alcohol swab, adhesive bandage, tourniquet, and gloves. Ensure the patient is in a comfortable position, preferably seated or lying down.

• 2. Patient preparation: Verify the patient’s identity by asking name and checking identification. Explain the procedure of blood collection to the patient. Obtain patient consent for blood collection. Apply the tourniquet above the selected site. It helps to locate veins easily.

• 3. Select the site for blood collection: The most common site is the antecubital fossa (inner elbow). Veins in the antecubital fossa are easily visible.

• 4. Hand Hygiene and Gloves: Wash hands thoroughly. Wear gloves.

• 5. Skin Disinfection: Clean the skin selected with an antiseptic swab in circular motion.

• 6. Needle Insertion: With the patient’s arm extended and veins exposed, use a sterile needle to puncture the vein. Once blood flow is established, release the tourniquet.

• 7. Blood Collection: Use appropriate blood collection tubes. Tubes may contain adhesives to prevent clotting or separation of blood clotting.

• 8. Needle Removal: Withdraw the needle gently for blood collection. Apply pressure to the puncture site with sterile gauze or cotton ball to prevent bleeding.

• 9. Labelling: Label each blood collection tube with the patient’s name, date, and any other required information.

• 10. Post-Collection Care: Instruct the patient to keep the puncture site elevated and apply continuous pressure until the bleeding stops.

• 11. Transporting Samples: Handle blood samples carefully to prevent hemolysis and contamination. Transport samples to the laboratory promptly.

• Q.15 Write a short note on lipids.

• Ans: Lipids are composed of carbon (C), hydrogen (H), and oxygen (H). Some lipids also contain phosphorus (P) and nitrogen (N). Lipids are organic molecules characterized by their hydrophobic (water-repellent) property. The following are some common chemical characteristics of lipids

  • 1. Fatty acids: Fatty acids are building blocks of lipids. Each fatty acid is composed of hydrocarbon chains. Hydrocarbon chains of fatty acids are composed of long chains of carbon atoms with a carboxyl group at one end (-COOH). The nature of fatty acids in lipids decides the chemical properties of lipids. There are two types of fatty acids.

  • · Unsaturated fatty acids: Unsaturated fatty acids consist of an unsaturated hydrocarbon chain. Hydrocarbon chain containing one or more double bonds.

  • · Saturated hydrocarbon: Saturated fatty acids consist of a saturated hydrocarbon chain. The saturated hydrocarbon chain contains only single bonds.

  • 2. Triglycerides (Triacylglycerols): Triglycerides are the most common type of lipid in the biological body. Triglycerides are composed of three fatty acid molecules. Triglycerides store energy.

  • 3. Phospholipids: The chemical structure of phospholipids and triglycerides are similar. Two fatty acids and one phosphate group are attached to a glycerol molecule in phospholipids. Phospholipids molecule has one polar end called the hydrophilic end or head of phospholipids molecule. Another end of the phospholipids molecule is the non-polar end called the hydrophobic end or tail of phospholipids molecules. Phospholipids form a lipid bilayer in the cell membrane.

  • 4. Sterols: Sterols are the lipids. They consist of four interconnected carbon rings. Example cholesterol.

• Q.16 Write down the different types of Hazards.

• Ans: In basic chemistry, the main hazards are Biological hazards, Chemical hazards, fire hazards, and apparatus hazards.

  • Biological Hazards: Microorganisms, Toxins, Allergens, Biological Materials, etc

  • Chemical Hazards: Toxic Substances, Corrosive Materials, Flammable and Combustible Materials, Explosive Materials, Carcinogens, etc.

  • Fire Hazards: The conditions, materials, or situations that increase the risk of a fire occurrence leading to harm to people, property, and the environment are called fire hazards.

  • Apparatus Hazards: Dangers associated with the equipment and instruments used for experimental and analytical purposes are apparatus hazards. The following are some common apparatus hazards in chemistry and biochemistry laboratories Glass wares, Pressure Equipments (Autoclaves, reactors) Mechanical Hazards (stirrer, mixer, etc), Electrical Hazards (Electronic instruments) Chemical Hazards, Radiation Hazard, etc.

• Q.17 Why cleaning glassware is important in the laboratory?

• Ans: Clean glassware ensures the accuracy, reliability, and safety of experimental procedures and results. The following are the importance of cleaning glassware is important in a laboratory

  • 1. Contamination Prevention: Contaminants present in the apparatus affect the results of tests. It affects the accuracy of the measurement and result. Clean apparatus prevents cross-contamination.

  • 2. Ensure Reproducibility: Regular cleaning of glassware maintains experimental conditions. This contributes reproducibility of the result.

  • 3. Quality Control: Clean glassware is for quality control in the laboratory.

  • 4. Maintain glassware longevity: Regular cleaning extends the life span of glassware. It ensures the reliability of the data.

  • 5. Good Laboratory Practices (GLP): Clean glassware reflects the attention, discipline, and commitment of laboratory technicians to maintain a high standard of hygiene and accuracy.

  • 6. Prevent Unexpected Chemical Reactions: Clean glassware minimizes the risk of unexpected chemical reactions during testing.

  • 7. Safety Consideration: Clean glass apparatus controls the apparatus hazards associated with chemical interactions.

• Q.18 Write down the difference between hard water and soft water.

Ans:

• 1. Definition: Hard water contains a high concentration of dissolved minerals like calcium ions, magnesium ions, etc. Soft water contains a very low concentration of dissolved minerals.

• 2. Scaling: Hard water leaves a high amount of the scale (deposits) on the apparatus wall, and Soft water leaves a very low amount of the scale on the apparatus wall.

• 3. Cleaning: Hard water reduces the cleaning ability of cleaning agents used in the laboratory. Soft water improves the cleaning ability of the cleaning agents.

• 4. Rinsing: Hard water makes it difficult to wash out all cleaning agents from the apparatus. Soft water makes a smooth washout of cleaning agents from the apparatus.

• 5. Taste: Hard water has a characteristic taste due to the several minerals. Soft water has taste called “clean taste".

• Q.19 What is the importance of Acid and base?

• (Wrong question. The basic chemistry syllabus mentions studying the physiological importance of acids and bases”. We will discuss mentioned in the syllabus )

Ans: Physiological importance of Acid and Base in the human system

Acid and base participate in various physiological processes within human the body. Acid-base in the human body is essential for several biochemical reactions inside human the body.

• 1. pH Balance: Normal body fluid pH is 7.4. That is slightly alkaline. This pH is important for the proper functioning of the various biochemicals, enzymes, proteins, carbohydrates, metabolic reactions, etc inside human the body.

• 2. Digestion: Foods are digested inside GIT. Digestion of food depends upon pH of the the GIT. Such as protein digestion is fast inside an acidic medium in the stomach carbohydrate digestion is fast inside an alkaline medium of the intestine.

• 3. Enzyme activity: Enzymes act as catalytic reactions inside the body. OptimuThe optimality of the enzyme is pH sensitive.

• 4. Cellular functions: Cell functions depend upon pH.

• 5. Blood buffering: Blood pH is 7.4. Blood acts as a buffer. Disturbance in blood buffering is life-threatening.

• 6. Respiratory regulation: Breathing regulates concentre concentration of carbon dioxide in the blood. Carbon dioxide concentration in the blood affects blood pH. Body The body's respiratory rate is by this blood pH.

• 7. Kidney function: The excretion rate in the kidney is regulated by the acid-base system of the human body.

• Q.20 What are the good qualities of water?

  • Ans: Importance of Water quality in the clinical laboratory: Maintaining water quality in the clinical laboratory is essential for accurate and reliable test results, proper functioning of equipment, and ensuring the best possible patient care. The following are good quality of water.

  • 1. Universal Solvent: Water is an excellent solvent for chemical reactions. It is considered a universal solvent.

  • 2. Versatility in states: Water exists in three states: solid (ice), liquid (water), and gas (water vapor). in states:

  • 3. Good conductor of electricity;

  • 4. Transparent to visible light

  • 5. Chemical Neutrality: Water pH is 7 thus water is chemically neutral. This makes water suitable for several chemical reactions.

  • 6. Reagent preparation: Reagents require distilled water to ensure the effectiveness and quality of the reagent. Normal water may contain contaminants that affect the composition of reagents and their effectiveness.

  • 7. Cohesion and adhesion: Water molecules stick with each other (cohesion) and also stick with the most surfaces (adhesion).

  • 8. High heat capacity: It can absorb large heat without any decomposition in water's chemical nature.

• Q.21 Write a note on any one law of photometry.

  • Ans: Laws of photometry: The law of photometry is a principle that relates the brightness or luminance of an object to its physical properties such as luminous flux and the observer’s distance from the object. The fundamental law of photometry is the inverse square law. The inverse square law of photometry states that the intensity of brightness of light from a point source decreases with the square of the distance.

• This helps to explain why objects become dim as you move from a light source.

• Q.22 What are the characteristics of solutions?

  • Ans:

  • 1. Homogeneity: Solutions are homogeneous mixtures. There are no visible boundaries between solute and solvent. This solution has a Uniform Composition.

  • 2. Stability: Solutions are physically stable.

  • 3. Particle Size: The particle size of the solute is less than 1 nanometer. This makes the solution transparent.

  • 4. Clarity and transparency: The solution allows visible light to pass.

  • 5. Conductivity: Most solutions are good conductors of electricity.

  • 6. Colligative properties: Concentration of solute in solution affects the colligative properties of the solution, like vapor pressure, osmotic pressure freezing point, and boiling point,

Dr Pramila Singh

• SECTION-D

Note: Long answer type questions. Attempt any two

questions out of three questions. (2x8=16)

• Q.23 Give the classification of carbohydrates and their nutritional effect on the human body.

• Ans: Carbohydrates are organic compounds composed of carbon (C), hydrogen (H), and oxygen (O) atoms. Examples: Glucose, Sucrose, Starch, etc.

Classification of carbohydrates: Carbohydrates are classified into the following three classes

• 1. Monosaccharide: Monosaccharides are the simplest carbohydrates. They cannot be further hydrolyzed to smaller sugars. The general formula of monosaccharide is (CH2O)n. “n” represents the number of carbon atoms in the monosaccharide. Examples of common monosaccharides are glucose, fructose, and galactose. Monosaccharide is the basic building block of complex carbohydrates.

• 2. Disaccharide: Disaccharide consists of two monosaccharide molecules. Both monosaccharide molecules are connected with glycosidic bonds. Examples are sucrose (glucose + fructose), maltose (glucose + glucose), and lactose (glucose + galactose). Hydrolysis of one molecule of disaccharide releases two molecules of monosaccharide.

• 3. Oligosaccharide: Oligosaccharide consists of three or more monosaccharide molecules. Hydrolysis of oligosaccharides produces three or more molecules of monosaccharide.

• 4. Polysaccharide: Polysaccharide consists of more than ten molecules of monosaccharide. Hydrolysis of polysaccharides produces more than ten molecules of monosaccharide. They are not sweet in taste and are also called non-sugar. Examples: Starch, cellulose, glycogen, etc.

• Starch: Plants store glucose as starch as a source of energy. It consists of a long chain of glucose.

• Glycogen: Animals store glucose as glycogen as a source of energy. It consists of a large number of glucose molecules.

• Cellulose: Cellulose is a structural component of plant cell wall. It consists of a large number of glucose molecules. The arrangement of glucose molecules in cellulose is different from the arrangement of glucose molecules in starch and glycogen.

Nutritional effect of carbohydrates on the human body: Carbohydrates provide energy and support various physiological functions in the human body.

• 1. Energy Source: Carbohydrates are primary sources of energy for the human body

• 2. Brain Functions: The brain utilizes 80% of carbohydrates consumed by the human body.

• 3. Muscle Fuel: Carbohydrates provide energy for the physical activity of the body.

• 4. Digestive Health: Fibers in food are carbohydrates. It is essential for digestive health.

• 5. Nutrient Absorption: Carbohydrates help to absorb some food components. For example, glucose helps in the absorption of sodium and water in the small intestine.

• 6. Heart health: Soluble fibers in diet improve heart health.

• Q.24 Explain about the following a) Surface Tension, b) Luminous Intensity.

Ans: Surface Tension: Surface tension is a property of the liquid surface. It is attraction force (cohesion force) between liquid molecules at the surface of the liquid. Strong attraction force will be on the molecules at the liquid surface towards the interior rather than towards the air. Surface tension makes the liquid surface behave like elastic.

• Several properties of the liquid like drops formation, droplets formation, capillary action, floating of molecules or insects on the water surface, etc are due to surface tension.

Luminous Intensity:

• Luminous intensity is a measure of the light amount that is emitted, transmitted, or received. It states the brightness of the light source. The standard unit of luminous intensity is the candela (cd) under the International System of Units (SI).

• Luminous intensity is related to luminous flux. Luminous flux is the total amount of visible light emitted by a source in all directions. Luminous intensity is the luminous flux per unit solid angle.

• Luminous intensity is measured by the photometers. The photometer measures the brightness of light in a controlled manner.

• Luminous intensity is used in lighting designing, optical engineering, and the development of lighting standards. It ensures that lighting systems meet specific brightness requirements.

• Top of Form

• Q.25 Write a detailed note on GLP.

Assuring Good Laboratory Practices (GLP) in Basic Chemistry

Assuring Good Laboratory Practices (GLP) in basic chemistry is essential to ensure the reliability and integrity of experiment results. GLP is a set of principles and standards that guide the conduct of non-clinical safety studies. The following points are considered to ensure GLP in basic chemistry.

• 1. Training and Qualification: Ensure laboratory personnel are adequately trained and qualified for their assigned task. Maintain records of training, qualification, and experience for each individual.

• 2. Standard Operating Procedures (SOPs): Develop and implement SOPs for all laboratory activities like sample preparation, analytical procedure, and equipment operation. SOPs should be well-documented, regularly updated, and accessible to all relevant personnel.

• 3. Documentation and Record Keeping: Documents all aspects of laboratory work, including raw data, calculations, observations, and results. Keep accurate and detailed records of equipment calibration, maintenance, and any deviations from established procedures.

• 4. Instrumentation Calibration and Maintenance: Regularly calibrate and maintain laboratory instruments to ensure the accuracy and reliability of measurements. Document all calibration procedures, calibration frequency, and calibration results.

• 5. Quality Control (QC) Checks: Implement routine quality control checks by using known standards and reference materials. Document quality control procedures and results. Take corrective actions if deviation is identified.

• 6. Sample Handling and Storage: Establish procedures for proper sample handling, storage, and disposal. Clearly label all samples and ensure they are stored in appropriate conditions to maintain their integrity.

• 7. Data Integrity: Implement a data protection system. Use electronic signatures, secure data storage, and backup systems. Ensures to implementation  ALCOA principles (Attribute, Legible, Contemporaneous, Original, and Accurate principles).

• 8. Personnel Hygiene and Safety: Promote and enforce good laboratory hygiene practices to ensure the safety of personnel and the integrity of experiments. Provide appropriate personal protective equipment (PPE) and ensure its proper use.

• 9. Internal Audits and Inspections: Conduct regular internal audits to assess compliance with GLP standards. Address any non-compliance issues promptly and implement corrective measures.

• 10. External Audits and Accreditation: Consider seeking external accreditation from regulatory bodies or organizations to demonstrate compliance with GLP standards. Participate in external audits to validate and improve laboratory practices.