Answer:
19.8 %
Explanation:
V% = ( V of solute \ 100 ml of solution ) ×100% =
the volume of the solute in 100ml solition = 20 ml
42.9 ml of solute ----------215 ml solution
× ----------- 100 ml solution
42.6 × 100 ml ÷ 215 ml
= 19.8 ml of solute
the V% = (19.8 ÷ 100) ×100% = 19.8%
Answer:
Irrigation is the artificial process of applying controlled amounts of water to land to assist in production of crops. Irrigation helps to grow agricultural crops, maintain landscapes, and revegetate disturbed soils in dry areas and during periods of less than average rainfall.
Answer:
The element that glows in signs is xenon.
Explanation:
Xenon is a chemical element with the symbol Xe and atomic number 54. It is a colorless, dense, odorless noble gas found in Earth's atmosphere in trace amounts. Xenon is used in flash lamps, arc lamps, and as a general anesthetic. Xenon emits a blue or lavenderish glow when excited by electrical discharge, it emits a band of emission lines that span the visual spectrum, but the most intense lines occur in the region of blue light, producing the coloration.
