Grade 5 - Changes in Matter Flashcards
A change that affects only the physical properties of matter is called ______.
physical change
A change in the phase or state of matter is another example of ________.
physical change
True or False: A change in phase may occur when heat is added or removed from a substance.
True.
A liquid turning into gas undergoes a process called ______.
evaporation
When heated, some solids turn directly into gas without passing through the liquid phase. This process is called _______.
sublimation
When some gases cool down, they can turn directly into solids through a process called ________.
deposition
Provide the following process for each corresponding physical change.
- Melting
- Freezing
- Evaporation
- Condensation
- Deposition
- Sublimation
Process:
- Melting - Solid to liquid
- Freezing - Liquid to solid
- Evaporation- Liquid to gas
- Condensation - Gas to liquid
- Deposition - Gas to solid
- Sublimation - Solid to gas
A new substance is formed when a _________ takes place.
chemical change
True or False: The composition of matter is altered when a chemical change takes place.
True
True or False: A chemical change may happen in the presence or absence of oxygen or with the application of heat.
True
Give some examples or evidence that indicate chemical change.
Changes in color, taste, and smell.
The release of light and heat.
The formation of gas.
True or False: Chemical change may be hastened or slowed down by changes in temperature.
True
True or False: Heat can cause some substances to decompose and form new substances.
True
The decomposition of substance due to heat is called ______.
thermal decomposition
It is a form of chemical change or reaction that involves heating and breaking down of a complex substance into two or more simpler substances
thermal decomposition
The changes in the appearance of iron and some fruits are due to _______.
oxidation.
Refers to any process in which oxygen combines with an element or substance, either slowly as in the rusting of iron, or rapidly, as in the burning of paper.
Oxidation
Give some examples of oxidation.
Rust formation
Aerobic respiration
Production of vinegar
Browning of fruits
Food spoilage
Rust is formed by the reaction of?
iron (FE)
oxygen (O2)
Iron and oxygen react and form a new substance called
iron oxide (rust)
True or False: Iron and oxygen have characteristics and properties that are different from those of rust.
True
Aerobic means?
air
True or False: Aerobic respiration requires oxygen.
True
The equation for aerobic respiration is.
glucose + oxygen -> carbon dioxide + water + energy
Is the simplest form of sugar that we get from the food that we eat.
Glucose
True or False: Vinegar may be prepared from any fruit juice that contains sugar (glucose).
True
The mixture of acetic acid and water is commonly known as
vinegar
True or False: Acetic acid is what gives vinegar its sour taste.
True
True or False: Food such as apples, pears, potatoes, and bananas turn brown when exposed to air.
True
Give some examples of slowing down the oxidation process of food (apples, pears, potatoes or bananas)?
- Refrigerate fruits and vegetables or place them in ice water after cutting them.
- By cooking
- Adding a small amount of lemon juice or calamansi juice to the fruit to make it acidic can also slow down the oxidation process.
True or False: Chemical change in food spoilage is accompanied by the formation of bubbles, discoloration, foul odor and unpleasant taste.
True
Bacteria that require oxygen to grow are called _____.
aerobes
Bacteria that can only grow in the absence of oxygen are called ______.
anaerobes
True or False: Molds and most yeasts are aerobes that cause food to spoil.
True
Certain enzymes that are naturally present in food are called _____.
oxidizing enzymes
True or False: Spontaneous reaction of oxygen with fats in foods also causes the formation of substances with unpleasant strong odors and flavors. This may cause illnesses such as diarrhea, nausea, or vomiting.
True
