WorksheetsIntroducing Elements, Compounds and Mixtures
Total questions: 12
Worksheet time: 8mins
Sodium and chlorine chemically mixed form -
(a)
The periodic table lists the number of known what?
Compounds
Mixtures
Elements
Alkalis
The number of elements in the periodic table is (a) .
Uranus and Neptune are mainly made of hydrogen, helium, methane and water. Which of them are compounds?
Hydrogen
Methane
Water
Helium
The San Francisco region is called the ____ Valley because of the high presence of ____ , used to make transistors. It is famous as a tech hub.
silicon
nickel
tungsten
silver
Higher Order Thinking Skills
In an electric bulb, we usually pump gases like krypton or argon to form a layer around the filament and not allow air as a whole inside. Why? (Think about the dangers of allowing air as a whole in)
The air conducts electricity and will give us electric shock, but pure krypton and argon prevent it from reaching.
Krypton and argon is abundant in the atmosphere and cheap, so people just use them.
They are noble gases, which means that they have low reactivity rates, as a result preventing a fore from happening.
It conducts heat, so that the bulb makes you warm and happy and can be used as a portable heater.
Who was John Dalton?
A scientist from England
An archaeologist from the United States
A rich businessperson from Kenya
An astronomer from India
Which of the following are points of Dalton’s atomic theory?
All matter is made of atoms. Atoms are indivisible and indestructible.
Elements are only found in the Solar System.
Compounds are formed by a combination of two or more different kinds of atoms.
A chemical reaction is a rearrangement of atoms.
All compounds are conductors of electricity.
What are the components of an atom
Protons
Megatrons
Electrons
Neutrons
Positrons
What element has only one proton and one electron?
Chlorine (Cl)
Hydrogen (H)
Potassium (K)
Uranium (U)
Visualise a compound being created in a chemical reaction at the atomic level by the interaction of other atoms and describe what may be happening.
Glucose (a type of sugar) is a compound made of which of the following elements?
Hydrogen
Phosphorus
Oxygen
Nitrogen
Carbon
