125 Each half life it divides by 2 the amount
1000/2=500
500/2=250
250/2=125
TL;DR: The make of an aircraft is the name of the designer (for example, Boeing) and the model of an aircraft (also called the type) is the designation for the general design of the aircraft (for example, 737). It looks like "basic model" is just an older term for "model".
Answer: 714 g Al2O3
Explanation: Solution attached
First convert mass of O2 to moles
Do the mole ratio between O2 and Al2O3 from the balanced equation.
Convert moles of Al2O3 to mass using its molar mass.
Some physical properties that a pencil would have is, color, density, texture, hardness (in this case the lead is soft). phase (liquid,solid gas), shape, size. physical properties describe the look and feel of a substance. I hope this helps
