Explanation:
Pure subsance is a substance that is made up of only one type of particle - each piece is the same throughout.
Being present before the reaction but not after means it's no the same (it couldve evaporated)
Answer:
0.00559 mol
Explanation:
The following data were obtained from the question:
V = 140mL = 0.14L
T = 296K
P = 98.2kPa = 98200Pa
Recall: 101325Pa = 1atm
98200Pa = 98200/101325 = 0.97atm
R = 0.082atm.L/Kmol
n =?
The number of mole (n) can be obtained as follows:
PV = nRT
n = PV /RT
n = (0.97x0.14)/(0.082x296)
n = 0.00559 mol
Therefore, the number of mole of the gas present is 0.00559 mol
Explanation:
The 2019 water crisis in Chennai has made us realize the importance of saving water more than ever. Water, as we all know, is a finite resource without which our planet would be a barren wasteland. Today with our increasing population it would be logical to say that our water consumption has also increased. And with increasing demand and lesser supply, water scarcity arises. Our ancestors who had foreseen the potential dangers of water scarcity had developed methods to conserve water that was suited for the varied terrain of the Tamil-speaking kingdoms.
Traditional Rainwater Conservation methods of Tamil Nadu
Eri
There are no perennial rivers in Tamil Nadu except the Thamirabharani River which flows through Thirunelveli district. And so, several hundred years ago a simple system was devised to utilize the rainwater to the fullest. An Eri or tank system is one of the oldest forms of water conservation systems in India. Many Eris are still in use in Tamil Nadu and play an active role in irrigation. They act as water reservoirs and flood control systems. They prevent soil erosion, recharge groundwater, and prevent wastage of runoff water during heavy rainfall.
Kudimaramathu
Kudimaramathu is one of the old traditional practice of stakeholders participating in the maintenance and management of irrigation systems. During earlier days, citizens of a village used to actively participate in maintaining the water bodies of their village by deepening and widening the lakes and ponds and restoring the water bodies back to their original form. The silt, rich in nutrients, collected in the process would be used by the farmers themselves in their field. A sense of collective ownership ensured the continued survival of the water bodies.
Answer:
76.1 amu
Explanation:
Let us recall that isomers refer to two different compounds with the same molecular formula but different atom to atom connectivity and different chemical properties. When two compounds are isomers, we can essentially represent them with exactly the same molecular formula.
Now propane-1,2-diol and propane-1,3-diol are both represented by the molecular formula C3H8O2 since they are isomers of each other. When two compounds have the same molecular formula, they must essentially have the same molecular mass. Hence the molecular mass of propane-1,3-diol is also 76.1 amu.
<u>Answer:</u>
The correct answer option is B) 2.0 M.
<u>Explanation:</u>
We are given the number of grams of NaOH (Sodium Chloride) which are dissolved in 750 milliliters of water and we are to find its molarity.
We know the formula of molarity:
<em>Molarity = (mass * 1000) / (volume * molecular mass) </em>
Volume = 750 ml = 750 cm
Molecular mass = 40
Mass = 60 grams
Substituting these values in the above formula:
Molarity = 
= 2.0 M
