The number of mole of Ca reacted is:
4.86 g Ca/ (40.08 g/mol Ca)= 0.121 mol Ca
Because Ca reacted completely with oxygen and there is 2 mol Ca, there is 1 mol O2 reacted.
Total mass of oxygen that reacted is:
0.121 mol Ca* (1mol O2/ 2 mol Ca)* (32 g O2/ 1 mol O2)= 1.94 g O2 reacted.
Hope this would help~
Answer:
34g
Explanation:
We'll begin by writing the balanced equation for the reaction. This is illustrated below:
H2S + 2AgNO3 —> 2HNO3 + Ag2S
Next, we shall determine the number of mole of H2S required to react with 2 moles of AgNO3.
This is illustrated below:
From the balanced equation above,
We can see that 1 mole of H2S is required to react completely with 2 moles of AgNO3.
Finally, we shall convert 1 mole of H2S to grams. This is shown below:
Number of mole H2S = 1 mole
Molar mass of H2S = (2x1) + 32 = 34g/mol
Mass = number of mole x molar Mass
Mass of H2S = 1 x 34
Mass of H2S = 34g
Therefore, 34g of H2S is needed to react with 2 moles of AgNO3.
<h2>Answer : Option B) The hematite particles rearrange to form a new substance.</h2><h3>Explanation :</h3>
Hematite particles when gets rearranged to form a new substance, is an example of a chemical change.
As a chemical changes is usually a change where a substance undergoes a chemical change and forms a new substance; which cannot be easily reversed into reactants by any simple physical methods.
In this example the hematite ore forms a new substance by an irreversible chemical change.
<u><em>Answer:</em></u>
- A pure substance that contains more than one atom is called a compound.
<u><em>Explanation:</em></u>
- Compounds are formed by combination of atoms by a fixed ratio. They have their own characteristic features.
- Pure substances are further broken down into elements and compounds. A compound can be destroyed by chemical means. It might be broken down into simpler compounds, into its elements or a combination of the two.
<u><em>Example </em></u>
- H2SO4 which is formed by combination of three different atoms like H, S and O.
Temperature. In case you have ever baked, you can relate to this. For example, when you make caramel, you simply put the caramel on a boiling hot pan and sit back and watch it. It always goes fastest this way.