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Digestive System Disorders: Causes, Symptoms, Treatment & Prevention Guide

Disorders of the Digestive System - Causes, Symptoms & Treatment Disorders of the Digestive System: Causes, Symptoms, Treatment & Prevention 1. Introduction to Digestive Disorders The digestive system breaks down food and absorbs nutrients. Disorders like acid reflux, IBS, or ulcers can interfere with these processes. Understanding symptoms, causes, and treatments is essential for maintaining gut health. 2. Common Digestive System Disorders Acid Reflux (GERD): Stomach acid flows into the esophagus causing heartburn. Peptic Ulcers: Open sores in the stomach or small intestine. Irritable Bowel Syndrome (IBS): Affects bowel habits with cramping and bloating. Constipation: Infrequent or painful bowel movements. Diarrhea: Loose, frequent stools. Inflammatory Bowel Disease (IBD): Includes Crohn's disease and ulcerative colitis. Gallstones: Block bile flow, causing pain an...
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Class 9 Chemistry Chapter 1: States of Matter and Phase Changes – MCQs with Answers & Explanations

 


MCQ 1:

Matter is present in neon signs in the state of:
(a) Supercritical fluid
(b) Plasma ✅
(c) Gas
(d) Liquid crystal

Explanation:
Neon signs work using a type of matter called plasma, which is an ionized gas with free electrons and positively charged ions. When an electric current passes through neon gas, it ionizes and emits light, producing the characteristic glow of neon signs.

MCQ 2:

Hazardous effects of shopping bags are studied in:
(a) Geochemistry
(b) Inorganic chemistry
(c) Analytical Chemistry
(d) Environmental chemistry ✅

Explanation:
Environmental chemistry deals with the study of pollutants, including plastic shopping bags, and their effects on the environment. It focuses on the impact of chemicals on air, water, and soil.

MCQ 3:

The man-made polymer is:
(a) Starch
(b) Polystyrene ✅
(c) Protein
(d) Cellulose

Explanation:
Polystyrene is a synthetic polymer commonly used in plastic products, whereas starch, proteins, and cellulose are naturally occurring biopolymers.

MCQ 4:

The allotropic form of sulfur is:
(a) Brass
(b) Rhombic ✅
(c) Graphite
(d) Bronze

Explanation:
Sulfur exists in several allotropic forms, with rhombic sulfur being its most stable crystalline form at room temperature. Brass and bronze are metal alloys, while graphite is an allotrope of carbon.

MCQ 5:

Which liquid among the following is a colloidal solution?
(a) Milk ✅
(b) Slaked lime used for whitewash
(c) Vinegar solution
(d) Mixture of AgCl in water

Explanation:
A colloid is a mixture where small particles are dispersed in a medium without settling. Milk is a colloidal solution because fat globules are suspended in water.

MCQ 6:

Which of the following is a heterogeneous mixture?
(a) A solution of calcium hydroxide in water
(b) A solution of potassium nitrate in water
(c) Hot chocolate
(d) Concrete mixture ✅

Explanation:
A heterogeneous mixture has non-uniform composition. Concrete is heterogeneous because it consists of cement, sand, gravel, and water, which do not mix uniformly.

MCQ 7:

A state of matter whose properties are between those of liquids and crystalline solids:
(a) Liquid crystal ✅
(b) Supercritical fluid
(c) Plasma
(d) Dark matter

Explanation:
Liquid crystals have properties intermediate between liquids and solid crystals. They flow like liquids but have some ordered molecular structure like solids, making them useful in LCD screens.

MCQ 8:

When tiny particles of a substance are dispersed through a medium, the mixture is called:
(a) True solution
(b) Colloid ✅
(c) Suspension
(d) Heterogeneous mixture

Explanation:
A colloid is a mixture where small particles are dispersed but do not settle. Examples include fog, milk, and gelatin.

MCQ 9:

A solution of KClO₃ has a solubility of about 13.2g per 100 cm³ at 40°C. How will its solubility be affected if you decrease the temperature?
(a) The solubility will increase
(b) The solubility will decrease ✅
(c) The solubility will remain the same
(d) The solubility will first increase with temperature and then decrease

Explanation:
For most solids, solubility decreases as temperature decreases. Since KClO₃ (potassium chlorate) dissolves better in hot water, reducing temperature lowers its solubility.

MCQ 10:

You are studying the rate of hydrolysis of organic compound starch under different temperature conditions. In which branch of chemistry does this topic fall?
(a) Organic Chemistry
(b) Analytical Chemistry
(c) Biochemistry
(d) Physical Chemistry ✅

Explanation:
Physical chemistry deals with reaction rates, energy changes, and the effect of temperature on reactions. Since hydrolysis of starch involves a reaction rate study, it falls under physical chemistry.

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