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Answer:
Explanation:
The glass (which does not crystallize even though it is accepted) of a window is NOT a mineral, since it is neither a substance of natural origin (although it is manufactured from natural components) nor does it have a defined crystalline structure, that is, the atoms they are not arranged in an orderly and regular way along axes and planes forming flat faces that keep a symmetry.
Remember that a mineral is defined as a solid, inorganic, homogeneous substance, of natural origin, with a crystalline structure and a determined and well-defined chemical composition within narrow margins and that has regular and characteristic physical properties.
Answer:

Explanation:
Molarity is found by dividing the moles of solute by liters of solution.

We are given grams of a compound and milliliters of solution, so we must make 2 conversions.
1. Gram to Moles
We must use the molar mass. First, use the Periodic Table to find the molar masses of the individual elements.
- C: 12.011 g/mol
- H: 1.008 g/mol
- O: 15.999 g/mol
Next, look at the formula and note the subscripts. This tells us the number of atoms in 1 molecule. We multiply the molar mass of each element by its subscript.
6(12.011)+12(1.008)+6(15.999)=180.156 g/mol
Use this number as a ratio.

Multiply by the given number of grams.

Flip the fraction and divide.


2. Milliliters to Liters
There are 1000 milliliters in 1 liter.

Multiply by 2500 mL.


3. Calculate Molarity
Finally, divide the moles by the liters.


The original measurement has 2 significant figures, so our answer must have the same. That is the hundredth place and the 3 tells us to leave the 7.

1 mole per liter is also equal to 1 M.

Answer:
₁₁A
Explanation:
Atomic radius
As we move from left to right across the periodic table the number of valance electrons in an atom increase. The atomic size tend to decrease in same period of periodic table because the electrons are added with in the same shell. When the electron are added, at the same time protons are also added in the nucleus. The positive charge is going to increase and this charge is greater in effect than the charge of electrons.
This effect lead to the greater nuclear attraction. The electrons are pull towards the nucleus and valance shell get closer to the nucleus. As a result of this greater nuclear attraction atomic radius decreases.
So in given elements consider A₁₁, B₁₂, C₁₃ ans D₁₇ as sodium, magnesium, aluminium and chlorine. This is the third period and as we move form sodium to chlorine atomic radius decreases. That's why sodium has greater size.
As we move down the group atomic radii increased with increase of atomic number. The addition of electron in next level cause the atomic radii to increased. The hold of nucleus on valance shell become weaker because of shielding of electrons thus size of atom increased