Answer:
b. growth in the size of the mineral grains
Explanation:
Non-foliated texture shown by a metamorphic change is depicted by growth in the size of the mineral grains.
- Examples of non-foliated metamorphic rocks are quartzite and marble.
- In these metamorphic rocks, mineral grains are not aligned with their long axis.
- Non-foliated texture occurs under high temperature and low pressure conditions.
- As minerals are able to grow, the size can be used to show a metamorphic change.
Answer:
Empirical formula: BH3
Molecular Formula: B2H6
Explanation:
To solve the exercise, we need to know how many boron atoms and how many hydrogen atoms the compound has. We know that of the total weight of the compound, 78.14% correspond to boron and 21.86% to hydrogen. As the weight of the compound is between 27 g and 28 g, using the above percentages we can solve that the compound has between 21.1 g and 21.8 g of boron, and between 5.9 g and 6.1 g of hydrogen:
100% _____ 27 g
78.14% _____ x = 78.14% * 27g / 100% = 21.1 g boron
100% ______27 g
21.86% ______ x = 21.86% * 27g / 100% = 5.9 g hydrogen
100% _____ 28 g
78.14% _____ x = 78.14% * 28g / 100% = 21.8 g boron
100% _____ 28g
21.86% _____ x = 21.86% * 28g / 100% = 6.1 g hydrogen
So, if the atomic weight of boron is 10.8 g, there must be two boron atoms in the compound that sum 21.6 g. The weight of hydrogen is 1 g, so the compound must have six hydrogen atoms.
The molecular formula represents the real amount of atoms that form a compound. Therefore, the molecular formula of the compound is B2H6.
The empirical formula is the minimum expression that represents the proportion of atoms in a compound. For example, ethane has 2 carbon atoms and 6 hydrogen atoms, so its molecular formula is C2H6, however, its empirical formula is CH3. Therefore, the empirical formula of the boron compound is BH3.
Answer:
<u>Optical purity = 76.9231 %</u>
<u>Specific rotation of mixture = - 97.6923 °</u>
Explanation:
The mass of the racemic mixture = 3 g
It means it contains R enantiomer = 1.5 g
S enantiomer = 1.5 g
Amount of Pure R = 10 g
Total R = 11.5 g
Total volume = 500 mL + 500 mL = 1000 mL = 1 L
[R] = 11.5 g/L
[S] = 1.5 g/L
Enantiomeric excess = 
= 
= 76.9231 %
<u>Optical purity = 76.9231 %</u>
Also,
Optical purity = 
Optical rotation of pure enantiomer = −127 °
<u>Specific rotation of mixture = - 97.6923 °</u>
Answer: 899 g
Explanation:
Since the mass of a mole of diatomic chlorine is about 70.9 g/mol, this means that 875 grams is about 875/70.9 = 12.3 mol.
Hence, we know that chlorine is the limiting reactant, and that about 12.3 moles of chlorine will be consumed.
This means that 12.3(2)=24.6 grams of HCl will be produced, which will have a mass of about (24.6)(36.46)=899 g
