The amount of Al2O3 in moles= 1.11 moles while in grams = 113.22 grams
<em><u>calculation</u></em>
2 Al + Fe2O3 → 2Fe + Al2O3
step 1: find the moles of Al by use of <u><em>moles= mass/molar mass </em></u>formula
= 60.0/27= 2.22 moles
Step 2: use the mole ratio to determine the moles of Al2O3.
The mole ratio of Al : Al2O3 is 2: 1 therefore the moles of Al2O3= 2.22/2=1.11 moles
Step 3: finds the mass of Al2O3 by us of <u><em>mass= moles x molar mass</em></u><em> </em>formula.
The molar mass of Al2O3 = (2x27) +( 16 x3) = 102 g/mol
mass is therefore= 102 g/mol x 1.11= 113.22 grams
The cloud with those characteristics is #1
Answer:
B. Gravity held the pieces of forming planets together.
c. Gravity pulled most of the matter into the center of the solar system
D. Gravity caused the planets and Sun to have spherical shapes.
Explanation:
When a collection of grains pulled together by their gravitational forces would keep in by the gravity of a star, it would eventually became bigger to the point a planet was formed.
The sun's strong gravitational force pulled most of the matter around it to the center of the solar system.
The spherical shape of planets is a result of their gravity pulling equally from all sides, shaping it into a sphere.
Answer:
A chemical change
Explanation:
The marshmallow turning brown and bubbling implies that a chemical change has taken place.
For chemical changes to occur, we observe any of the following:
- a new kind of matter is formed.
- it is always accompanied by energy changes
- the process is not easily reversible
- it involves a change in mass
- requires considerable amount of energy.
ii. Two signs that shows a chemical change has taken place is that:
- bubbles are being formed as it is roasted and it implies that new substances have been formed.
- also, significant amount of heat energy is supplied for the roasting.
B.
Spring tides occur during a new/full moon. The sun, moon and earth form a straight line during these phases.