Chemistry, asked by Meep, 1 year ago

Could you help and check? Please?


Maria and Miquel were enjoying the fireworks when they got into a chemistry argument. Maria insisted that the fireworks were the result of a chemical reaction. Miguel disagreed. What would you tell them to solve this argument.  

A) It is a change of state, solid to gas, due to the addition of energy.  

B) The color changes and the release of energy indicate a chemical reaction.   

C) Because the fuse were lit and energy is added, it is a physical reaction.   

D) It is an endothermic reaction because energy was added; therefore it is a chemical reaction,


Molecules are different from atoms because they...  

A) have less energy.   

B) are much smaller. <<i dont think this one is right

C) have unique properties.   

D) contain chemical bonds.<<<<<i think its this one


A student takes four samples of a silver, metallic solid and and subjects each piece to different treatment.

Piece 1: The solid is hammered into a flat sheet.
Piece 2: The solid is heated in a flame until it melts.
Piece 3: The solid fizzes when acid is dropped on the surface.
Piece 4: The solid is place in a beaker of water and it floats.

Which piece, when treated, indicates a chemical change?   

A) piece 1  

B) piece 2

C) piece 3 <<<<<<<this one is it, right?

D) piece 4


The Venn diagram describes a phase change from solid to gas phase between the areas marked. (pic 1)  Answer: C?



A + B → C + D 

If there are 4 grams of product produced by the chemical reaction, how many grams of reactant were consumed? Answer: its 4, right?


Summarize the Venn diagram.  (pic 2)

A) Compounds are found inside the matter of atoms.     <<<<<i think its this one

B) A pure substance may contain subatomic particles but not atoms.   

C) Compounds are the most basic form of matter. They combine to form larger atoms.  

D) Atoms are the most basic form of matter. They combine to form larger electrically stable compounds.

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Answers

Answered by kvnmurty
63
1. Maria and Miquel =   B) color change and release of energy due to a chemical reaction.  After reaction, the products formed have less internal energy as compared to the reactants.

2. Molecules are different from atoms as they contain chemical bonds. 
    atoms and molecules have SOME common properties. molecules are bigger.

3. Piece 3.   Other pieces undergo a change in physical state.  Piece 3 undergoes a chemical change in forming a compound with silver. Like if the acid is Hydrogen chloride, then silver chloride and hydrogen gas are formed. The sizzling or fizzing is due to gas Hydrogen, as it forms bubbles and escapes in to air.

4. In the venn diagram indicating physical states of matter :
     the area that indicates the phase change from solid to gas or the other way is the phase  marked as "sublimation" or "deposition."

5.    A+B -> C+D    In any chemical reaction, mass is conserved. SO the total mass of the compounds products formed is same as that of the reactants.

6.  venn diagram. for atoms and molecules.
       D) atoms are the most basic form of nature.  they combine to form larger electrically stable compounds.   Atoms are combined to form molecules.  Atoms consist of sub atomic particles.    atoms are found in the matter of compounds. not the other way.




Meep: Thank you so so much :)
kvnmurty: you are welcome. select as best answer.
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