To determine the standard heat of reaction, ΔHrxn°, let's apply the Hess' Law.
ΔHrxn° = ∑(ν×ΔHf° of products) - ∑(ν×ΔHf° of reactants)
where
ν si the stoichiometric coefficient of the substances in the reaction
ΔHf° is the standard heat of formation
The ΔHf° for the substances are the following:
CH₃OH(l) = -238.4 kJ/mol
CH₄(g) = -74.7 kJ/mol
O₂(g) = 0 kJ/mol
ΔHrxn° = (1 mol×-74.7 kJ/mol) - ∑(1 mol×-238.4 kJ/mol)
ΔHrxn° = +163.7 kJ
Question:
A chemistry student needs of 10 g isopropenylbenzene for an experiment. He has available 120 g of a 42.7% w/w solution of isopropenylbenzene in acetone. Calculate the mass of solution the student should use. If there's not enough solution, press the "No solution" button.
Answer:
The answer to the question is as follows
The mass of solution the student should use is 23.42 g.
Explanation:
To solve the question we note the following
A solution containing 42.7 % w/w of isopropenylbenzene in acetone has 42.7 g of isopropenylbenzene in 100 grams of the solution
Therefore we have 10 g of isopropenylbenzene contained in
100 g * 10 g/ 42.7 g = 23.42 g of solution
Available solution = 120 g
Therefore the quantity to used from the available solution = 23.42 g of the isopropenylbenzene in acetone solution.
Answer: Option (d) is the correct answer.
Explanation:
Since the given formula is 
. According to cross method formula, magnesium has +2 charge so, 
is multiplied by 2.
Thus, 1 molecule of magnesium phosphate will contain 2 atoms of phosphorus.
Therefore, three molecules of magnesium phosphate contains following number of atoms.
Hence, we can conclude that there are 6 atoms of phosphorus in three molecules of magnesium phosphate, .
Explanation:
Osmosis is the movement of water molecules, across a semipermeable membrane, from a hypotonic solution to a hypertonic solution
Osmosis is critical in the maintenance of the right amount of water in the cells an organism. Water is a universal solvent and is especially important for biochemical activities of a cell. Osmosis maintains the right water homeostasis in cells.
Osmosis is useful in the absorption of water by the roots of the plants and the maintenance of transpirational pull that ensures herbecious plants remain upright.
Osmosis enables the opening and closing of plant stomata hence regulating the loss of water by the plants.
Learn More:
For more on osmosis check out;
brainly.com/question/6199270
brainly.com/question/6320563
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Periodic Trend:
The Atomic radius of atoms generally decreases from left to right across a period
Group Trend:
The atomic radius of atoms generally increases from top to bottom within a group. As atomic number increases down a group, there is a increase in the positive nuclear charge, however the co-occurring increase in the number of orbitals wins out, increasing the atomic radius down a group in the periodic table
Answer :
The Atom with the greatest atomic radius is chlorine. Fluorine can be ruled out because it is in the same period as oxygen and further to the right down the period. Chlorine has the largest atomic size because it is farthest down the group of any of the above elements listed.
