Answer:
Physical change: A,C ,D, F, H, I
Chemical Change: B, E, G, J, K
Answer:
The attractive force between them decreases
Explanation:
This is because they become localised.
Answer is: The total energy in the system remains the same as the decrease in chemical energy equals the increase in thermal and radiant energy.
The law of conservation of energy states that the total energy of an isolated system remains constant; energy can neither be created nor destroyed; it can only be transformed or transferred from one form (in this example chemical energy) to another (in this example thermal and radiant energy).
Radiant energy or light is the only kind of energy we can see with our eyes. Light have different wavelenght and different color.
Chemical energy - this type of energy is often found in things like batteries or food.
Answer:
<u>The incorrect choice is the last one:</u>
- <em>In the Leucipo and Democritus atomic model, electrons had negative charges.</em>
Explanation:
The translation of the question is:
Choose the incorrect statement. *
- Matter is everything that has mass and occupies volume.
- Mass and weight are different quantities. Mass is a measure of how much matter an object has, and weight is a measure of the gravitational pull force suffered by the object.
- Dalton's atomic model has similarities to the atomic model described by Leucipo and Democritus.
- Dalton thought that atoms of the same element could not combine, as they developed mutual repulsion.
- In the Leucipo and Democritus atomic model, electrons had negative charges.
<h2>Solution</h2>
The <em>last statement is false</em> because Leucipo and Democritus thought that the atom was an indivisible particle. This is, they did not think there were subatomic particles, such as electrons. Furthermore, the idea of a particle with a negative charge was developed much time (centuries) later.
As for the other statements:
- <em>Matter is everything that has mass and occupies volume</em>: this is the current definition of matter; for instance, wood, air, atoms, have mass and occupy volume. Thougths, feelings do not have either mass or occupy a volume, they are not matter.
- <em>Mass and weight are different quantities</em>. <em>Mass is a measure of how much matter an object has, and weight is a measure of the gravitational pull force suffered by the object</em>. Indeed, the mass is determined by the number of atoms of the substance, but weight is the force of attraction from Earth (or other planet, if the object is in other planet). Mass does not change with the location; weight does.
- <em>Dalton's atomic model has similarities to the atomic model described by Leucipo and Democritus</em>: sure. This is a hystorical question. Leucippus and Democritus were two Greek phylosophers who believed that the matter was formed by tiny solid particles, the atom.
- <em>Dalton thought that atoms of the same element could not combine, as they developed mutual repulsion</em>. In the times of Dalton, when he developed the law of multiple proportions, atoms of a same kind were thought to repel each other.
<h2>Answer : Option D) Heterogeneous mixture</h2><h3>Explanation : </h3>
A mixture in which particles are not evenly distributed and particles keep their unique properties are called as heterogeneous mixture.
Usually, in heterogeneous mixture the substances are not evenly distributed and they can be easily separated through any physical methods. Also the components retains their original/unique properties in the mixture. It usually contains various particles from different substances that are not uniformly distributed throughout the mixture.
