Nguyên tố A có cấu hình electron phân lớp cuối cùng là 4p3. A phải

How do Newton's laws of motion explain why it is important to keep the ice smooth on a hockey rink so that players

andriy [413]

Answer:

How do Newton's laws of motion explain why it is important to keep the ice smooth on a hockey rink so that players can pass a puck as quickly as possible? Smooth ice reduces the unbalanced forces that would slow the hockey puck. A skydiver falls toward the ground at a constant velocity.

Explanation:

3 0

2 years ago

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Consider the statement: "Copper is a red-brown element obtained from copper sulfide ores by heating the ores in air, which forms

Misha Larkins [42]

Answer:

1, just I) color.

Explanation:

Physical properties are the properties that can be observed without changing the composition of a substance, such as color, temperature, density, and boiling point.

A physical change is a change in the substance that only modifies its aggregation state, such as solidification, and boiling.

Chemical properties are the properties that need a reaction to being observed, such as the combustibility, which needs a combustion reaction to being quantified.

When a chemical reaction occurs, and the composition of the substance change, it's a chemical change.

So, the heating copper with carbon is a chemical reaction, and purification by electrolysis is too. Color is the only physical property.

4 0

3 years ago

Why is pseudo science not considered real science

swat32

Pseudo-science is not considered real science because it is not testable.

Answer: Option A

<u>Explanation:</u>

Pseudoscience primarily includes beliefs, theories or practices that are somehow incompatible with the scientific facts. The pseudoscience can’t be tested on the basis of science.

Let’s take an example of astrology. Some people believe that stars and other celestial bodies draw a significant impact on their life i.e. Good or bad thing it's just because their stars are working either in a positive or negative manner.

But, this belief doesn’t have any well-proved or authentic background over which the whole concept can rely on. Hence, pseudoscience is not taken as a real science as a lack of strong proves.

8 0

3 years ago

For the following systems at equilibrium C: CaCO3(s) ⇌ CaO(s)+CO2(g) ΔH=+178 kJ/mol D: PCl3(g)+Cl2(g) ⇌ PCl5(g) ΔH=−88 kJ/mol cl

Rama09 [41]

Explanation:

C: $CaCO_3(s)\rightleftharpoons CaO(s)+CO_2(g)$ ΔH=+178 kJ/mol

For an endothermic reaction, heat is getting absorbed during a chemical reaction and is written on the reactant side.

$A+\text{heat}\rightleftharpoons B$

Any change in the equilibrium is studied on the basis of Le-Chatelier's principle. This principle states that if there is any change in the variables of the reaction, the equilibrium will shift in the direction to minimize the effect.

Treat heat as a reactant and on increasing a reactant at equilibrium, shifts the reaction in the forward direction.

Increase temperature → increase in heat → forward direction

Decrease temperature → decease in heat → backward direction

System C - Increase temperature : Reaction will move forward

System C - Decrease temperature : Reaction will move backward

D: $PCl_3(g)+Cl_2(g)\rightleftharpoons PCl_5(g)$ ΔH=−88 kJ/mol

The total enthalpy of the reaction comes out to be negative .

The temperature of the surrounding will increase.

For an exothermic reaction, heat is released during a chemical reaction and is written on the product side.

$A\rightleftharpoons B+\text{ heat}$

Any change in the equilibrium is studied on the basis of Le-Chatelier's principle. This principle states that if there is any change in the variables of the reaction, the equilibrium will shift in the direction to minimize the effect.

Treat heat as a product and on increasing a product at equilibrium, shifts the reaction in the backward direction.

Increase temperature → increase in heat → backward direction

Decrease temperature → decease in heat → forward direction

System D - Increase temperature : Reaction will move backward

System D - Decrease temperature : Reaction will move forward

7 0

2 years ago

Many organisms in an ecosystem copete with each other for resources. What might different species of trees in a forest ecosystem

sineoko [7]

Territory and energy sources

4 0

3 years ago

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