CHEMISTRY POST TEST

Imagine Benjamin, Ethan, and Avery are on a space adventure, discovering new planets! They found a curious object and want to measure the amount of matter it contains. This measure is known as the object's ________________. Can you help them figure it out?

• volume

• density

• mass

• solubility

Answer explanation

The correct measure of the amount of matter in an object is its mass. Mass is the quantity of matter in an object, which can be measured using various methods such as weighing scales or balances.

Imagine Grace, Sophia, and Isla are in a science lab, observing a mysterious substance. They're trying to figure out what characteristics of this substance they can note without altering its very essence. What is this type of observation called?

• physican change

• physical property

• chemical change

• chemical property

Answer explanation

The correct choice is 'physical property' because observing characteristics without altering the essence of a substance falls under physical properties, not chemical changes or properties.

Imagine Priya and Luna are in a magical lab where they mix potions. Everything they have before mixing equals everything they have after the mix. What law does this remind you of?

• law of conservation of mass

• law of conservation of energy

• chemical change

• chemical property

Answer explanation

The scenario described aligns with the law of conservation of mass, which states that mass is neither created nor destroyed in a chemical reaction, only transformed.

Alright, science detectives! Evelyn, Nora, and Aria have stumbled upon a curious case. They need your help to solve this mystery:

A characteristic of matter that can only be observed when matter is transformed into a completely new kind of matter. What is it?

• Chemical

• Physical

Answer explanation

The correct answer is 'Chemical' because a chemical change is the only type of change where matter is transformed into a completely new kind of matter, revealing new characteristics.

• element
• compound
• mixture of elements
• mixture of compounds

Imagine James and Samuel are on a thrilling science adventure, and they've just discovered a mysterious sample at point A. As they excitedly watch it move towards point E, they notice something fascinating happening! What kind of process is the sample undergoing?

• exothermic process by releasing heat to the surroundings

• exothermic process by absorbing heat from the surroundings

• endothermic process by releasing heat to the surroundings

• endothermic process by absorbing heat from the surroundings

Answer explanation

The correct choice is 'endothermic process by absorbing heat from the surroundings' because the sample is absorbing heat as it moves towards point E, indicating an endothermic process.

Imagine Arjun and Avery are in a lab, excitedly mixing different substances. They end up creating something entirely new! What type of matter have they just made, considering it's from 2 or more substances chemically combining?

• element

• compound

• mixture

• property

Answer explanation

Arjun and Avery have created a compound by chemically combining 2 or more substances, resulting in a new type of matter.

Imagine Kai, Aria, and Emma are in a science lab, watching a potion bubble and fizz! What does this exciting scene suggest about the potion?

• Stretching

• Tearing

• Compressing

• Bubbles

Answer explanation

The presence of bubbles and fizzing in the potion suggests that it is undergoing a chemical reaction, creating gas bubbles. This indicates the potion is bubbling.

Imagine Abigail and Charlotte are on a science adventure when they stumble upon a mysterious particle. This particle, much like a superhero of the atomic world, boasts two protons and two neutrons, wielding a mighty 2+ charge. It's none other than the equivalent of a helium-4 nucleus, famously represented by the symbol α. This tiny but mighty force is known for making its grand exit during the spectacular event of radioactive decay. What do Abigail and Charlotte call this particle?

• alpha particle

• beta particle

• gamma rays

• radiation

Answer explanation

Abigail and Charlotte call this particle an alpha particle because it is a helium-4 nucleus with two protons, two neutrons, and a 2+ charge, known for its role in radioactive decay.

Imagine Kai and Ava are in a science lab, experimenting with radiation from a radioactive source. They notice that when they direct this radiation between two electrically charged plates, one type of radiation is deflected toward a negatively charged plate. This radiation is made up of alpha particles. What type of radiation is it?

• radiation

• alpha radiation

• gamma rays

• beta radiation

Answer explanation

The correct type of radiation deflected towards the negatively charged plate is alpha radiation, as described in the scenario.