Answer:
Cement is a combination of calcium, silicone, aluminum, iron and lots of other ingredients to make side walks, home made crafts, etc. The person who invented concrete is Joseph Aspdin.
Explanation:
The compound : C₄₀H₄₄N₄O
<h3>Further explanation</h3>
The empirical formula is the smallest comparison of atoms of compound =mole ratio of the components
The principle of determining empirical formula
• Determine the mass ratio of the constituent elements of the compound.
• Determine the mole ratio by dividing the percentage by the atomic mass
The mol ratio of composition : C : H : N : O

Answer: oxygen
There is the s,p,d and f blocks, from groups 1-2 that is the s block, 13-18 that’s the p block, 3-12 is the d block and the f would be lanthanide(#57-71) and actinide (#89-103).
Answer : The mass of of water present in the jar is, 298.79 g
Solution : Given,
Mass of barium nitrate = 27 g
The solubility of barium nitrate at
is 9.02 gram per 100 ml of water.
As, 9.02 gram of barium nitrate present in 100 ml of water
So, 27 gram of barium nitrate present in
of water
The volume of water is 299.33 ml.
As we know that the density of water at
is 0.9982 g/ml
Now we have to calculate the mass of water.


Therefore, the mass of of water present in the jar is, 298.79 g