Chemistry

Explain the Effect of surface area, Concentration on Rate of Reaction.  What is Collision Theory? Effect of surface area: Ever tried to light a bonfire or a camp fire. Which burns more quickly -a block of wood or a pile of wood shavings? Small pieces of solids, especially powders, react faster than large pieces. As we increase the surface area, the rate of reaction increases. Collision theory: Effect of Concentration:  As we increase the concentration, the rate of reaction increases.

What is an Element? Element : Elements contain only one type of atom. In the early ages, only nine elements (carbon, gold, silver, tin, mercury, lead, copper, iron and sulphur) were known. At that time, it was considered that elements were the substances that could not be broken down into simpler units by ordinary chemical processes. Until the end of nineteenth century, sixty-three elements had been discovered. Now 118 elements have been discovered, out of which 92 are naturally occurring elements. Modern definition of element is that it is a substance made up of same type of atoms, having same atomic number and cannot be decomposed into simple substances by ordinary chemical means . It means that each element is made up of unique type of atoms that have very specific properties. Elements occur in nature in free or combined form. All the naturally occurring elements found in the world have different percentages in the earth's crust, oceans and atmosphere . Table shows natur...

What is Cellular respiration? Cellular respiration: The energy is released when cells use oxygen to break down sugars in the process of cellular respiration. Cellular respiration occurs in the mitochondria.  Oxygen combines with sugars to release the energy your body uses to do work. During cellular respiration, plant and animal cells produce carbon dioxide and water as waste products. Equation: 

What is 'rate of reaction'?  Measuring rates of reaction. Rate of reaction: The rate of a reaction tells us how quickly a chemical reaction happens. During a reaction, we can measure how much reactant is used up in a certain time. On the other hand, we might choose to measure now much product is formed in a certain time. Measuring rates of reaction: Measure how quickly one of the reactants is being used up.

What is transpiration?  Guard Cells,  Opening & Closing of Stomata. Transpiration: The loss of water through a plant's leaves is called transpiration. When the leaf has plenty of water, the guard cells swell and pull the  stomata open.  This allows water  and air to leave the plant. When the plant is low on water, the  guard cells shrink.  This causes the  stomata to close, which prevents water  from escaping. Guard Cells: Guard cells  are located in the leaf epidermis and pairs of  guard cells  surround and form stomatal pores.

What is Photosynthesis?  Define, Explain all the process  Mechanism of Photosynthesis,  Z-Scheme,  Calvin Cycle,  Role of Chlorophyll. Photosynthesis: •        It is an anabolic process •        Important component of Bioenergetics •        Important Biochemical pathway •        All life depends on it Define: •        Synthesis of Glucose •        From CO2 and H2O •        Presence of Sunlight & Chlorophyll •        O2 as a by-product Where it Occurs: •        In Plants •        Some Protists •        Some Bacteria Equation: Raw Material: •        CO2 •        H2O Intake of H...

Unit 1  Lesson 4: The Abbasid Empire The reign of the Abbasid Empire Its accomplishments and achievements on different levels The important figures in this period and the downfall of such an empire Lesson objectives: 1) identify the events that led to the rise and later downfall of the Abbasid Empire 2) list facts about some of the important figures in that age 3) define the period referred to as the golden age of Islam The leader of the Abbasid Empire: Al Abbas = a descendent of prophet Mohammad (PBUH) who started the new empire after invading Damascus (capital of the Umayyad Empire) and killing the last members there. Rise of the Empire: Treating people justly and equally Discrimination was not applied anymore Applying the religion of Islam kept everybody open to the diversity of the people around The religion of Islam was applied on the basis of equality The accomplishments of the empire: a. Moving the capital to Baghdad b. Attracting many poets, philosophers, and inventors c. T...

Define Bond Energy,  Activation Energy Differentiate between Breaking and Making Bond Energies.  Bond Energy: Energy needed to break different chemical bonds.  This energy is called the bond energy. Breaking Bond Energy: Breaking bonds requires energy.  It is endothermic. Making Bond Energy: Making new bonds gives out energy.  It is exothermic. Activation Energy: The minimum energy required to cause a reaction to occur.  The minimum amount of energy that is required to activate atoms  or molecules  to a condition in which they can undergo chemical change. 

Define Xylem, Phloem and Cambium.   Xylem: Xylem is a series of tubes that moves  water and minerals. Xylem  tissue conducts in only  one direction-up from the plant roots  to the leaves. Phloem: Phloem moves sugars that are made  in the plant's leaves to other parts  of the plant. It flows both up  and down in a plant. Phloem tissue is a two- way transport route. Cambium: The xylem and phloem layers in  a plant stem are separated by a layer  called the cambium. Xylem and phloem cells are produced  in the cambium.

Differentiate between  Gymnosperms and Angiosperms. There are two main types of seed plants : gymnosperms and angiosperms. Gymnosperms: A gymnosperm is a seed plant that does not produce a flower. Angiosperms: An angiosperm is a seed plant that produces flowers.

Unit 1  Lesson 3: The Umayyad Empire  Lesson objectives: Students should be able to: 1) identify the factors that led to the Umayyad extension 2) list facts about the Umayyad Empire 3) identify the factors that led to the downfall of the empire Umayyad Empire that extended from Spain and Morocco to the Indus River Valley. The beginning of the Islamic nation and the different empires which existed at the time of the Umayyads. The Umayyad Empire conquered such as Spain, India, and Libya (today) 1. they did not force people to follow the religion of Islam 2. non-followers had to pay more taxes than Muslims did 3. force was never used and destruction was prohibited Facts about the Umayyad Empire: a. Damascus flourished and became a main center of trade. b. All conquered areas spoke Arabic. c. All legal documents were in Arabic; same applied to the currency. d. They constructed major important buildings that exist up till date.

Differentiate between  Exothermic and Endothermic reactions. Exothermic Reaction: Exothermic reactions give out energy, often as heat. Endothermic Reaction: Endothermic reactions take in energy, often as heat.

Define vertebrate and invertebrate. The animal kingdom is one of the largest kingdoms. Vertebrate: A vertebrate is an animal with a backbone.  Invertebrate: An animal without a backbone is an invertebrate.

What is Classification? The act or process of classifying. The science of finding patterns. Classifying helps scientists identify, study,  group, and name organisms. Kingdom: Broadest group an organism  is classified into is a kingdom. One classification system used today divides  all organisms into six major groups called  kingdoms.