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3 years ago

When substances are formed that are different from the starting substances, a physical change has occurred. True False

2 answers:

4 0

False, because physical change does not involve the formation of substances. An example of physical change is change of state e.g water freezing .It is still water if you were to melt it.

Strike441 [17]3 years ago

3 0

Answer: The given statement is false.

Explanation:

Chemical change is defined as a change in which chemical composition and chemical properties of a substances changes.

For example: Rust formation on the iron.

Physical change is defined as a change in which form of the substance changes while chemical composition remains unchanged.

For example: Melting of an ice.

Here, new substance is formed which is different from the starting substance which means that a chemical change occurred.

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Elements that do not have full outer electron shells will donate, share, or take from other atoms. Choose the items that have th

Gnesinka [82]

Answer:

Ok...

Answer: YTH/JYG

Explanation:

AI+ZN+H=YTH

7 0

3 years ago

Explain why an insoluble compound added to water is considered a nonelectrolyte.

DaniilM [7]

Explanation:

A non-electrolyte is defined as a solution which does not contain any ions and hence, it is unable to conduct electricity.

For example, when a non-polar substance like $CCl_{4}$ is dissolved in water then it will not dissociate into ions.

As electricity is the flow of ions or electrons. So, a non-electrolyte solution is not able to conduct electricity.

Similarly, a compound that is insoluble in water will not dissociate into ions. Hence, this type of solution will not be able to conduct electricity.

8 0

3 years ago

¿Qué hecho indujo a Heisenberg a establecer el principio de incertidumbre?

yaroslaw [1]

Answer:

Here's what I find

Explanation:

Heisenberg observed that if we want to locate a moving electron, we must bounce photons off it.

However, this makes it recoil. By the time the photon returns to our eye, the electron will no longer be in the same place.

He concluded that there is a limit to the precision with which we can simultaneously measure the position and speed (momentum) of a particle.

The more precisely we know the electron's speed, the less precisely we know its position and vice versa.

The uncertainty in the product of the two values cannot be less than a fixed small number.

7 0

3 years ago

Write the ground-state electron configuration for the chloride ion.You may write either the full or condensed electron configura

dalvyx [7]

Answer:

$1s^22s^22p^63s^23p^6$

Explanation:

Chlorine is the element of group 17 and third period. The atomic number of chlorine is 17 and the symbol of the element is Cl.

The electronic configuration of the element chlorine is:-

$1s^22s^22p^63s^23p^5$

Chloride ion is formed when chlorine atom gain one more electron. So, the ground-state electron configuration for the chloride ion is:-

$1s^22s^22p^63s^23p^6$

8 0

3 years ago

Three mixtures were prepared from three very narrow molar mass distribution polystyrene samples with molar masses of 10,000, 30,

8_murik_8 [283]

Answer:

(a). 46,666.7 g/mol; 78,571.4 g/mol

(b). 86950g/mol; 46,666.7 g/mol.

(c). 86950g/mol; 43,333.33 g/mol

Explanation:

So, we are given the molar masses for the three samples as: 10,000, 30,000 and 100,000 g mol−1.

Thus, the equal number of molecule in each sample = ( 10,000 + 30,000 + 100,000 ) / 3 = 46,666.7 g/mol.

The average molar mass = [ ( 10,000)^2 + (30,000)^2 + 100,000)^2] ÷ 10,000 + 30,000 + 100,000 = 78,571. 4 g/mol.

(b). The equal masses of each sample = 3/[ ( 1/ 10,000) + (1/30,000 ) + (1/100,000) ] = 20930.23 g/mol.

Average molar mass = ( 10,000 + 30,000 + 100,000 ) / 3 = 46,666.7 g/mol.

(c). Equal masses of the two samples = (0.145 × 10,000) + (0.855 × 100,000)/ 0.145 + 0.855 = 86950g/mol.

The weight average molar mass = 1.7 + 10,000 + 100,000/ 1.7 + 1 = 43,333.33 g/mol.

6 0

3 years ago