Which of these particles is the smallest?
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an atom
a nucleus
a proton
a compound
The smallest particle among these options is an atom.
Matter can undergo physical and chemical changes. A physical change is a change of matter from one form to another without a change in chemical properties. Which process is an example of a physical change?
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iron rusting in rain
candle burning in jar
salt dissolving in water
chicken cooking in oven
An example of a physical change is salt dissolving in water. This is because in this process, the salt changes its physical state and breaks down into individual salt ions, but the chemical composition of the salt remains the same.
Alison mixes baking soda and vinegar in a clear glass container. She places a blue balloon over the mouth of the container. Which condition tells Alison that a chemical change is taking place?
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The balloon fills and expands.
The mixture is cloudy in appearance.
The balloon gets lighter blue as it expands.
The container holds a mixture of a solid and liquid.
The condition that tells Alison that a chemical change is taking place is when the balloon fills and expands. This indicates that a gas is being produced as a result of a chemical reaction between the baking soda and vinegar.
The starting products of a chemical reaction are 92.6g of Hg and 7.4g of oxygen (O) gas. A scientist hypothesizes that the mass of the final product will be 100g total. What law supports the scientists hypothesis?
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Law of Conservation of Elements
Law of Conservation of Energy
Law of Conservation of Mass
Law of Conservation of Atoms
The law that supports the scientist's hypothesis is the Law of Conservation of Mass. According to this law, the total mass of the reactants in a chemical reaction is equal to the total mass of the products. In this case, if the starting products have a combined mass of 100g, the law predicts that the final product will also have a mass of 100g.
Sean fell while riding his green bicycle last year. He bent the fender and scratched the paint down to the metal. Sean’s bicycle was outside all winter and now is beginning to rust where the fender is damaged. Which evidence tells Sean that a chemical change is taking place on his bike?
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The paint is scratched.
The metal fender is bent.
The metal is beginning to turn orange.
The bicycle sat in the weather all winter.
The evidence that tells Sean a chemical change is taking place on his bike is that the metal is beginning to turn orange. This indicates that the metal is undergoing a chemical reaction with oxygen in the air, resulting in the formation of rust.
To determine which of these particles is the smallest, let's consider each option and their respective sizes.
1. Atom: Atoms are the basic building blocks of matter. They consist of a nucleus, which contains protons and neutrons, surrounded by electrons. Atoms are generally very small, but they are not the smallest particles.
2. Nucleus: The nucleus is the central part of an atom that contains protons and neutrons. It is relatively small compared to the entire atom, but it is not the smallest particle.
3. Proton: Protons are subatomic particles found in the nucleus of an atom. They have a positive electric charge. Protons are smaller than the nucleus but larger than some other particles.
4. Compound: A compound is made up of two or more different elements chemically combined. It consists of molecules, which are composed of atoms. Compounds are not individual particles themselves, so they cannot be considered the smallest particle.
Based on these explanations, the smallest particle among the options provided is the proton. However, it's important to note that there are even smaller particles, such as quarks, which make up protons and neutrons.