Answer:
This is an example of chemical change because the Kool aid dissolved and turned the water red
Answer:
Turgor pressure in plants. Turgor pressure within cells is regulated by osmosis and this also causes the cell wall to expand during growth.
Explanation:
I hope that helps
Answer:
259.497 mg, 58.84%
Explanation:
BaSO₄ → Ba²⁺ + SO₄²⁻
to calculate the mole of BaSO₄
mole BaSO₄ = mass given / molar mass = 403 mg / 233.38 g/mol = 1.7268 mol
comparing the mole ratio
1.7268 mol of BaSO₄ yields 1.7268 mol of Ba²⁺
403 mg BaSO₄ yields ( 1.7268 × 137.327 ) where 137.327 is the molar mass of Barium mol of Ba²⁺
441 mg BaSO₄ will yield ( 1.7268 × 137.327 × 441 mg ) / 403 mg = 259 .497 mg
mas percentage of the Barium compound = 259 .497 mg / 441 mg × 100 = 58.84%
Answer:
W = -10.3 kJ
Explanation:
During combustion, the system performs work and releases heat. Therefore, the change in internal energy is negative, and the change in enthalpy, which is equal to heat at constant pressure, is also negative. Work is then calculated by rearranging the equation for the change in internal energy:
w=ΔE−qp=−5084.3 kJ−(−5074.0 kJ)
The release of heat is much greater than the work performed by the system on its surroundings. The potential energy stored in the bonds of octane explains why considerably large amounts of energy can be lost by the system during combustion.
Answer:
Explanation:
Na₂S₂O₃ solution does not react with KI (it reacts with I₂), so it is simply diluting the KI, and we can use the dilution formula.
Data:
c₁ = 0.15 mol·L⁻¹; V₁ = 5 drops
V(Na₂S₂O₃) = 40 drops
Calculations:
(a) Calculate the total volume
V₂ = 5 + 40 = 45 drops
(b) Calculate the concentration
0.15 × 5 = c₂ × 45
0.75 = 45c₂
