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Due to which two nutrients, do children often suffer from the deficiency of weak bones that can lead to bone deformities?
Vitamin C and Vitamin A
Vitamin D and Calcium
Vitamin C and Calcium
Vitamin A and Vitamin D
Several metals and non-metals react constantly in the world around us. When magnesium reacts with oxygen during a reaction, what would be the ideal word equation for the reaction?
Magnesium + Oxygen —> Oxygen Magnesiate
Magnesium + Oxygen —> Magnesium Oxide
Magnesium + Oxygen —> Magnesium Oxide + Water
Magnesium + Oxygen —> Magnesium + Carbon Dioxide
Aria needs to make a salt solution for her school project. She needs to mix the salt and water in order to obtain the solution. Which of the following would be a better option with relation to its surface area to volume ratio, in order to achieve the salt solution in the least possible time:
Sea salt, as it decreases the surface area to volume ratio as it has tiny particles
Himalayan Rock Salt, this decreases the surface area to volume ratio as it is wider
Table Salt, this increases the surface area to volume ratio as it has several tiny particles
Himalayan Rock Salt, this increases the surface area to volume ratio as it is larger
When a car is driven, it uses fuel in order for it to function. A combustion reaction occurs simultaneously. During this reaction, energy is produced and transferred to the surroundings. Which of the following is not an example of how this energy can be transferred to the surroundings:
Motion of the car in the forward direction (Kinetic Energy)
Large noises as the car moves (Sound Energy)
Light sparks when the car brakes (Light Energy)
Heating of the car (Heat Energy)
A reaction that occurs in the atmosphere follows the following word equation:
Hydrogen Peroxide + Catalase —> Oxygen gas + Water + Catalase
Catalase is present before and after the reaction. What is the role of the Catalase in reaction?
It is an impurity
It is an enzyme
It is an unreactive solid
It is a gas in the atmosphere
Sara goes to the chemistry lab and observes all of the chemicals in the storage unit. On one of these chemicals that is unidentified, she observes the following symbol. What can she interpret from this symbol?
It is an oxidizing chemical
It is a flammable chemical
It is a corrosive chemical
It is a hazardous chemical
During a party, several balloons are released into the atmosphere. These balloons are filled with helium and float in the air because:
There is more air than helium
Helium gas is as dense as air
Helium is equally dense as air
Helium is less dense than air
An aeroplane departs from the airport to its destination. It flies East at 350km/hr for 3 hours, which force acts upon the aeroplane as it is suspended in the air and in which direction?
Upthrust in the east direction
Drag in the east Direction
Air Resistance in the west direction
Upthrust in the east direction
Oceanic voyages during the Age of Sail were fraught with danger. In 1949 Vasco da Gama, was a sailor on his first voyage, who lost 116 of 170 men as they reported malaise and sore joints.
Later on, they developed easily bruised skin, bleeding gums and reopening of old wounds. What was this mystery disease?
Every morning Samuel has a peanut butter and jelly sandwich for breakfast before he goes to school. He learnt online that consuming too many carbohydrates is bad for one's health, so he decided to perform a test to see if the sandwich he enjoys every morning contains starch. When he puts Iodine solution on the bread sample, what should he observe if it contains starch?
The sample stays brownish-yellow.
The sample expands to twice its original size
The sample turns purple in colour
The sample turns blue-black in colour
Formula One is an international auto racing competition that occurs every year, in which multiple cars compete for 1st position on the circuit. Lewis Hamilton, 7 time world champion is known for achieving the best results on the grid by using his famous Mercedes car. What is the hidden reason behind his car being able to achieve the fastest speed amongst the rest.
The car’s body is rounded at the edges
The body of the car is streamlined
The car has a rounded front/nose
The car has a large surface area to volume ratio
Liam tries to investigate the density of different materials by submerging them in a beaker filled with water. Observe the picture below and try to identify with relation to water, the density of the material:
Density cannot be determined from this experiment
The material is less dense than water
The material has a density that is equal to water
The material is more dense than water
These graphs show increases in greenhouse gasses in Earth’s atmosphere. As levels of
greenhouse gasses have increased, the temperature of the Earth’s surface has risen.
Which change has most likely contributed to a rise in surface temperatures on Earth?
Humans started frequently using automated technologies that released methane, CO2 and SO2
Farmers increasingly use chemical fertilizers that allow nitrogen and phosphorous to enter the water sources
The world birth rate increased to more than 250 births per 1,000 people per year.
Several people started using carbon-efficient modes of transport, decreasing the carbon footprint
The diagram shown below is that of the human digestive system. Which of the following processes occurs in that section of the system labeled above and what is its significance :
Ingestion: Increasing the surface area of food digested by breaking it into smaller molecules
Egestion: Rids the body of toxins and waste materials produced by cells
Absorption: Digestive Juices and large surface area enable more molecules of food to be absorbed
Defaecation: Addition of digestive juices to remove pathogens and help digest fats
Noah wanted to use his bicycle but he needed to inflate his deflated tires with air first. What would happen to the pressure inside the tires, as soon as the air has been pumped into it?
The pressure inside increases in the upwards direction
The pressure inside decreases in all directions
The pressure inside increases in the downwards direction
The pressure inside increases in all directions