Chemical systems and us Flashcards
Define acids(Arhenius theory)
Acids are substances that release hydrogen ions when they dissolve in water
Define bases(Arhenius theory)
A base is a substance that produces hydroxide ions when dissolved in water
Is vinegar an acid or base
Acid(Acetic)
Are fertilizers(ammonia) base or acid?
Base
Define acid(Bronsted-Lowry theory)
A Bronsted-lowry acid is defined as a proton (hydrogen ion) donor
Bronsted-lowry base
A Bronsted-lowry base is defined as a proton (hydrogen ion) acceptor
Difference between alkali and base
Alkali dissolve in water.
Define dissociation
The splitting of a substance into ions
Strong acid
A strong acid is an acid that dissociates almost completely in aqueous solutions
Weak acid
A weak acid is an acid that partially (or incompletely) dissociates in aqueous solutions
List three indicators
Indicators consist of pH levels, litmus paper, and universal indicators
Which indicator is capable differentiating between the strengths of acids and bases?
Universal indicator
Define concentration of a substance
The term concentration refers to how much of the substance there is in a given volume of solution
Define dilution
Dilution is the addition of solvent, which decreases the concentration of the solute in the solution.
Define concentration
Concentration is the removal of solvent, which increases the concentration of the solute in the solution.
Neutralization reaction
A neutralization reaction is a chemical reaction between an acid and a base. The reaction of an acid and a base will always produce a salt and water.
Is Na+ soluble or insoluble?
Soluble
Is silver(Ag+) soluble or insoluble?
Insoluble
Which four sulfates are insoluble?
Calcium, barium, lead, silver
Which carbonates are soluble?
Sodium, potassium, and ammonium
What does human digestive system have?
Alimentary canal, pharynx(throat), stomach, small intestine, large intestine, rectum, anus
Four processes of digestive system
Ingestion, digestion, absorption, egestion
Define ingestion
the process of taking in food, drink, or other substances into the body, primarily through the mouth and digestive system
Define Digestion process chemical changes
Chemical changes involve the action of digestive enzymes and other substances such as hydrochloric acid and bicarbonate.
Define Digestion process physical changes
Physical changes involve the mechanical action of the teeth and saliva, the three-layered muscular stomach wall that mixes the stomach contents, peristalsis along the alimentary canal and even bile which helps to expose fat droplets to the enzyme lipase.
Define absorption process
The structure of the small intestine is adapted to maximize and facilitate absorption. In the large intestine water gets removed from undigested substances such as fibre and other waste products which form faeces.
Define egestion process
Faeces are temporarily stored in the rectum until they are egested in the process of defecation.
Oesophagus purpose
Food is transported from the mouth to the stomach with the help of muscular movements called peristalsis
Purpose of pancreas
Secretes pancreatic juice containing digestive enzymes such as proteases, amulases, and lipases. Produces bicarbonates to neutralize the acidic pH from the stomach.
Rectum purpose
Faeces are egested from the body with the help of muscles in the rectum wall.
Large intestine purpose
Peristalsis continues to move the remaining mixture down the large intestine. Water and some ions are absorbed. Undigested food, faeces, becomes solid and gets stored waiting for egestion
Small intestine purpose
Food is moved down with the help of peristalsis and mixed with the digestive juices from the pancreas and the wall of the small intestine. Enzymes such as trypsin, lipase, and pancreatic amylase continue to break down the food into small nutrients that are absorbed into the bloodstream with the help of villi.
Elements and sugars in carbohydrates
Contain the elements C, H, O
Simple sugars such as glucose, fructose, and galactose.
Complex sugars(polysaccharides) made up of starch
What do fats(lipids) do
Source and storage of energy in the body; insulate the body and vital organs and structures; cell membranes and some hormones are made of fats.
Purpose of fiber
Gives a bulky consistency to food to help it move through the digestive system; slows down the absorption of some molecules such as sugars
Lipase enzyme
Produced in pancreas, performs functions in small intestine, breaks down fats, producers fatty acids, pH level 7
Amaylyse enzyme
Produced in salivary glands, performs function in mouth, breaks down starch(carbs) food, producers maltose, pH level 7
What process in the body maintains temperature?
Homeostasis
Three components of homeostasis
A receptor detect change inside or outside the body
A control centre to process sensory information and coordinate action - central nervous system
An effector to direct an appropriate response such as sweating and vasodilation to regulate temperature.
What does the hypothalamus do?
Measures the temperature of the blood flowing through it and collects information from temperature sensors around the body. It brings the temperature back to normal(37)
What happens in the body during cold condition?
Capillaries constrict(narrow) near the surface of the skin to conserve heat. Sweat secretion stops and hairs stand up trapping an insulating layer of air.
What happens in the body during hot conditions
capillaries dilate(widen) near the skin surface to lose heat to the environment. Sweat glands begin to create, causing heat loss by evaporation.
What happens when blood sugar is high?
The pancreas responds by releasing insulin.
Insulin: Stimulates glucose uptake by tissue cells (muscle, kidney, fat) and the formation of glycogen in the liver (from glucose).
What happens when blood sugar is low?
The pancreas responds by releasing glucagon.
Glucagon
Stimulates the breakdown of glycogen into glucose in the liver. Glucose is released into the blood
What does pestle and mortar do
Used to grind up solid chemicals into fine powder and crush solids into smaller pieces
