Skip to main content


Rates of Reaction

Rates of Reaction: The term "rate of reaction" means how quickly (or slowly ) a reaction happens. It also tells you at what rate the reactants are used up, or the products are formed in a chemical reaction. For calculating the rate of a chemical reaction, you will need the following: The mass (or the volume) of the reactants (or the products) at the beginning and the end of the reaction. The total amount of time for the reaction. Once you have both the values, just divide the change in the mass (or the volume) by the total time taken for the reaction. This will be the rate of the reaction. The rate of reactions is usually measured in: For change in mass : Grams per second (g s -1 ), or For change in volume : Cubic decimetre per second (dm 3 s -1 ) Important: Rate of reaction c
Recent posts

What are Similes and Metaphors and how to use them

Similes and Metaphors Grammar / Simile and Metaphor Level: Beginner (10 minute read) In English language, both similes and metaphors are used for making comparison between two things. This makes sentences interesting, while also stating or describing an important idea or fact. Let's look at what they are and how to use them. What is a Simile? A simile is a figure of speech where two unlike things are compared. It is a form of figurative language that uses the words "as" and "like". We use the words "as" or "like" in a simile. As another way to put it, Similes are figurative expressions that use "as" and "like". Similes make comparisons more interesting and vivid for the reader. In a simile, both “as” and “like” support the comparison in their own way. When the word “as” is used, usually, an adjective is also incl

Reactivity series of metals

Reactivity series When metals react with other substances the metal atoms form positive ions by loosing electrons (from their outermost shells). However, some metals tend to form ions more easily than others. This tendency of forming positive ions (by loosing electrons) is called reactivity. Metals can be arranged in a list in order of their reactivity , and such a list is called reactivity series . In a reactivity series , the most reactive element is, usually, placed at the top and the least reactive element at the bottom . The metals potassium, sodium, lithium, calcium, magnesium, aluminium, zinc, iron, tin, lead, copper, silver and gold can be arranged in the order of their reactivity from their reactions with water and dilute acids . The non-metals hydrogen and carbon are often included in the reactivity series as they are useful in extracting metals from their oxides (met

Acids, alkalis and salts

In this chapter you will learn: Acids and alkalis Reactions of acids What is neutralisation reactions? Strong and weak acids pH of acids and alkalies Neutralisation of acids and salt production Acids and alkalis An acid is a substance that produces Hydrogen ions (H+) in water. Acid Turns blue litmus paper red . Acidic solutions have pH values less than 7 . These are 7 strong acids: chloric acid, hydrobromic acid, hydrochloric acid, hydroiodic acid, nitric acid, perchloric acid, and sulfuric acid. Strong acids completely dissociate into ions , in water. Weak acids only partially dissociate. The pH scale is used to measure a solution is acidic , neutral , or alkalinie .

What are direct And indirect speech

What is Direct Speech?: Definition: When we repeat the actual words of the speaker, it is called direct speech . We use quotation marks or inverted commas . Examples: He said, "I am busy ." What is Indirect Speech?: Definition: When we do not repeat the speaker's actual words , it is called indirect or reported speech . We use our own words , without changing their meaning. We do not use quotation marks here. Examples: He said that he was happy . Reporting Verb: These are verbs which are used for citing or reporting another speaker's ideas . These can be used both in quoting or paraphrasing . Most commonly used reporting verbs are say and tell . For example: ( He said, She said, ) How to change direct speech in to indirect speech: 1. The word "that" is used as a conjunction between the reporting verb and the reported speech. 2. If the reporting verb is in present tense or future ten

30 Imperative sentence examples

What are Imperative Sentences? Imperative sentence definition: In English, sentences can be of different types, and hence can be classified in different ways. One way to classify them is by their function. With this in mind, sentences can be classified as declarative , imperative , interrogative , and exclamatory sentences. In this article we focus on imperative sentences. Imperative sentences are used: to give an order or a command to make a request to give instructions to offer advice , a suggestion or an invitation In an imperative sentence, the verb typically comes at the beginning, and the subject is altogether missing. More specifically, the subject is implied and often refers to the second-person, or "the reader". An imperative sentence ends with a period (.) or an exclamation mark (!) depending on the forcefulness of the command. Also,

What are Adverbs?

Adverbs, different types of adverbs and their examples: What Are Adverbs? Definition: An adverb is a single word , or a group of words , that modifies a verb , an adjective or another adverb. An adverb tells us when , where , how and in what manner an action is performed. Let's consider the following examples: James was sleeping peacefully . Sam walks gracefully . He is an extremely talented singer. Nina plays really confidently. Here the adverb "really" modifies the adverb "confidently" . Note: Many adverbs end in "ly" , but this is not always true. For example: ( fast, never, well, very, least, more, less, now, there ) Also, there are words, like "friendly" and "lovely" , that end in "ly" , but they are adjectives , not adverbs . Types of adverbs: 1. Adverb Of Time: An adverb of time tells us when something is done. T