All categories

2 years ago

1. Distinguish between physical and chemical changes. Include examples in your explanations.

Biology

2 answers:

Rashid [163]2 years ago

8 0

Answer:

Physical change

Any change to the physical properties of a substance is called a physical change.

Physical changes are usually reversible as no new substance is formed. It is the same substance but with changed physical properties.

Chemical change

A change in which one or more new substances are formed is called as a chemical change.

Usually a chemical change involves a chemical reaction, which forms new products.

Example : Rusting of Iron, or burning wood.

Explanation:

have a good day <3 sorry i could answer q1 only ill think baout the others..

777dan777 [17]2 years ago

7 0

Answer:

A physical change is one in which altering the substance doesn’t change its composition. In other words, this is a change in the form of a substance without the production of a new substance. Physical changes can include breaking up the substance into smaller pieces or altering its state of matter.

A chemical change does involve a change in the substance’s composition. Here the change in the composition of a given substance causes a new substance to be produced in place of the original substance. Burning a match is an example of a chemical change.

Elements, which are listed in the periodic table of elements, are substances that can’t be broken down any further by ordinary types of chemical change.

Compounds consist of two or more elements that are combined chemically in such a way that the elements themselves can no longer be identified by their individual properties.

Mixtures consist of two elements mingled together without combining chemically. The individual properties of each material are maintained.

Shape Volume

Solid Definite (holds shape) Definite (fixed volume)

Liquid No definite shape (takes the shape of the container) Definite (fixed volume)

Gas No definite shape (takes the shape of the container) No definite volume (takes the volume of the container, but will expand indefinitely if not contained)

Atomic mass is generally equal to the sum of the number of protons plus the number of neutrons in an atom. This can be found in reference charts and on the periodic table, typically below the element’s chemical symbol.

Molecular mass is found by adding up all of the atomic masses of all of the individual atoms in one molecule of a compound.

Location Charge

Proton nucleus positive

Neutron nucleus no charge (neutral)

Electron shells (orbitals) surrounding the nucleus negative

Dalton’s atomic theory makes the following assumptions:

All matter consists of small particles called atoms.

All atoms of the same element are alike in size, shape, and weight, but differ in these properties from the atoms of the other elements.

Chemical reactions take place between atoms, and even in the most violent chemical reactions, the atoms don’t break into pieces.

Atoms combine with other atoms to form molecules.

Explanation:

You might be interested in

Where does mechanical breakdown of food occurs?

Verizon [17]

There are lots of location that mechanical digestion occurs. But 2 common locations of mechanical breakdown of food (or physical digestion) occur in the mouth and in the duodenum.

Mechanical breakdown of food does not require enzymes, which is different from chemical digestion. Usually, the main function of mechanical digestion is to help speed up the chemical digestion later, usually by increasing the surface area of the food.

In the mouth, we chew the food. This can help increase the amount of surface area of the food we ate so that later on, the chemical digestion that requires enzymes such as amylase or protease will speed up. More enzymes can contact the food.

In duodenum, bile that are produced from the liver helps emulsify fats and lipids into small oil droplets. Again, this action can also help increase the surface area of the lipids so that the digestion of lipids with enzyme lipase would be more efficient. Note that bile is important because only enzyme lipase can digest lipids in the duodenum, so if bile is not produced, fats are hardly digested.

Other types of mechanical digestion may include the churning in stomach, or the squeezing of food in the oesophagus (peristalsis).

6 0

3 years ago

What is mostly likely elevation of the mountain below

solniwko [45]

From the contour line that is a combination of two line segments that connect but do not intersect, 500 and 750 represent elevation on the topographic map. There are 5 contour lines in between the given elevations 500 and 750, therefore, the contour interval is 50. Since the peak of the mountain is 2 contour lines from 750, the elevation of the mountain is 850. Hence, the answer is 871 meters.

3 0

3 years ago

Read 2 more answers

Que sucedería con la especie humana si debido a una futura mutación genética sus células no pudieran realizar los procesos de mi

MaRussiya [10]

Answer:

la vida no podría continuar sin los procesos de división celular

Explanation:

La mitosis es el proceso de división celular mediante el cual se producen dos células idénticas a partir de una sola célula. Durante la mitosis la célula crece y duplica la cantidad de ADN, con lo cual exactamente el mismo contenido de información genética es trasmitido a las sucesivas células que el proceso de mitosis va a dar origen. Por otra parte, la meiosis es un proceso celular en el cual se producen dos divisiones nucleares y citoplasmáticas (meiosis I y meiosis II) las cuales son precedidas por una fase de replicación del ADN. En la especie humana, la mitosis da lugar a células diploides (2n) con dos set completos de cromosomas homólogos, mientras que la meiosis da lugar a cuatro células haploides (n) llamadas gametos (el gameto masculino es el espermatozoide y el gameto femenino es el óvulo) las cuales contienen la mitad del número cromosómico al de la célula de origen. En organismos eucariotas pluricelulares tales como la especie humana, la función de la mitosis es producir más células somáticas (soma: cuerpo) con idéntico material genético, mientras que la función de la meiosis es producir células aptas para el proceso de reproducción, es decir, células con la mitad del material genético que se fusionarán para generar una célula diploide o zigoto a partir del cual y mediante sucesivas mitosis se desarrollará un organismo adulto.

5 0

3 years ago

This is alphabetical so which goas in order shimmer signal obscure nonsense and nominate please say it right

goblinko [34]

This is the order:
Nominate, Nonsense, Obscure, Shimmer, Signal

6 0

3 years ago

What could be a cause of melanoma?

Alik [6]

<span>Causes Of Melanoma. Ultraviolet rays Most skin cancers are caused by too much exposure to the sun's ultraviolet (UV) rays. The two types of UV rays that cause melanoma are UV-A and UV-B rays.</span>

5 0

3 years ago