b............................................
Answer:
0.109 g.
Explanation:
Equation of the reaction:
Na3PO4 + 3HCl --> 3NaCl + H3PO4
Number of moles of HCl = molar concentration × volume
= 0.1 × 0.04
= 0.004 mol.
By stoichiometry, 1 mole of Na3PO4 neutralises 3 moles of HCl. Therefore, number of moles of Na3PO4 = 0.004/3
= 0.0013 mol
Mass of Na3PO4 = molar mass × number of moles
= 0.0013 × 164
= 0.219 g
Since 50% of Na3PO4 was present in the sample. Let 100 g be the total mass of the substance
= 0.219 × 50 g/100 g
= 0.109 g.
Answer:
A. the prevailing westerlies
Answer:
See the answer below
Explanation:
Even though plants are rooted in the ground, they still move, exert <u>force,</u> and do<u> work</u>.
Plant cells have very strong cell walls that allow <u>pressure</u> to build up inside of the cell as water is absorbed. This pressure is called <u>turgor</u>.
When turgor pressure is high enough in a cell, the cell walls become <u>firm</u> and as a result, the cell becomes rigid and the plant is able to stand <u>tall</u> and<u> straight</u>.
When a plant does not get enough water, the turgor pressure inside of the cells <u>decreases.</u> A decrease in <u>pressure</u> pushing against the cell wall causes the cells to lose their <u>shape</u> and <u>shrink</u>. This causes the plant to begin to droop or <u>wilt</u>.
When the wilted plant gets enough water, the cells will become rigid again, and the plant will stand firm and straight once again.
1- false
2- true
3- true
4- false
5- true
6- false
7- true
8- true
9- true
10- false
Hope it helps :)