Answer:
15.3 %
Explanation:
Step 1: Given data
- Mass of the sample (ms): 230 g
- Mass of carbon (mC); 136.6 g
- Mass of hydrogen (mH): 26.4 g
- Mass of nitrogen (mN): 31.8 g
Step 2: Calculate the mass of oxygen (mO)
The mass of the sample is equal to the sum of the masses of all the elements.
ms = mC + mH + mN + mO
mO = ms - mC - mH - mN
mO = 230 g - 136.6 g - 26.4 g - 31.8 g
mO = 35.2 g
Step 3: Calculate the mass percent of oxygen
%O = (mO / ms) × 100% = (35.2 g / 230 g) × 100% = 15.3 %
Asteroids are made up of metals and rocky material , while comets are made up of ice ,dust and rocky material.
Answer:
The study of the human body as a machine for the performance of work has its foundations in three major areas of study—namely, mechanics, anatomy, and physiology; more specifically, biomechanics, musculoskeletal anatomy, and neuromuscular physiology. Explanation:
Answer:
9.0 moles of CaO
Explanation:
We have the reaction equation as follows;
Fe2O3 + Ca3(PO4)2 -------> 2FePO4 + 3CaO
Now we know from the equation that;
1 mole of iron III oxide yields 3 moles of CaO
Therefore;
3 moles of iron III oxide yields 3 * 3/1
= 9.0 moles of CaO
Quartz is a substance because the material has uniform properties throughout and is held together via chemical bonds.