Answer: B. a chemical change
Explanation:
Answer:- B: 
is the right answer.
Solution:- The balanced equation is:
We have been given with 8.75 grams of oxygen and asked to calculate the grams of hydrogen needed to react with given grams of oxygen according to the balanced equation.
From balanced equation, 1 mole of oxygen reacts with 2 moles of hydrogen.
So, let's convert grams of oxygen to moles and multiply it by the mole ratio to calculate the moles of hydrogen that are easily converted to grams on multiplying by it's molar mass.
The complete set up looks as:
=
Hence, the right option is B: .
Answer:
The third one makes the most sense
Answer:
Luster of aluminum is Silver-White.
Explanation:
Aluminium is a Silver-White metal which is extracted from the Bauxite ore which can be reddish brown, white, tan, grey-white and tan-yellow in color and have the minerals like Gibbsite, Boehmite and Diaspore which are the minerals of the aluminium.
The Bauxite is the rock from which the Bauxite ore is extracted which have the minerals of the aluminum.
The luster of a metal is the color and shine of it and its shiny appearance.
Aluminium is a light weight metal but have a moderate hardness which makes a wider use of it. Aluminium is used in many places where the weight of the material is kept light but its hardness can be increased by mixing some other metals in it making hard alloy with lighter weight.
It is used in transportation vehicles, buildings, and many other places like Air crafts as the weight should be kept controlled to give a perfect lift to the Air craft.
