Answer:
D
Explanation:
Firstly it is pertinent to know that, Electric force are due to the movement of electrons that is due to its gain and loss. This phenomenon is based on static electricity.
When the glass ruler is rubbed over the woolen sweater, the wool gets positively charged and the ruler gains electron to form negative charge.
Now if this charged is not earthed, the negative charged ruler attracts the uncharged bits of paper, as a result of which the paper gets attached to the ruler.
Answer:
Nitrate is a polyatomic ion with the molecular formula NO⁻₃ and a molecular mass of 62.0049 u. Organic compounds that contain the nitrate ester as a functional group are also called nitrates.
<span>Chemical Energy is energy stored in the bonds of chemical compounds (atoms and molecules). It is released in a chemical reaction, often producing heat as a by-product (exothermic reaction). Batteries, biomass, petroleum, natural gas, and coal are examples of stored chemical energy.
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A catalyst is a substance that increases the rate of a chemical reaction by lowering the activation energy without being used up in the reaction. After the reaction occurs, a catalyst returns to its original state and so catalysts can be used over and over again.
Answer:
The net chemical equation is:
Explanation:
Condictions for extraction of copper metal allow the reaction ocurrs.
First step yield 2 moles of 
, that later reacts with C, to poduce the copper metal.
Necessarily, reactions has to be balanced to know the proportion of each element.
In the first step oxygen (O2) replace sulfur (S), yielding sulfur dioxide and copper(I) oxide:
Next, copper(I) oxide reacts with carbon (C), yielding copper (Cu) and carbon monoxide:
At the end, to complete the net chemical reaction, it is necessary multiply second step for 2, since it is obtained two moles of from the first step. Then, we can sum both steps, reminding that species present in both terms are canceled.
