Answer:
4
10
Explanation:
The reaction equation is given as;
Ca(OH)₂ → Ca²⁺ + 2OH⁻
Concentration of Ca(OH)₂ = 5 x 10⁻⁵M
Unknown:
pOH of the solution = ?
pH of the solution = ?
Solution:
Solve for the pOH of this solution using the expression below obtained from the ionic product of water;
pOH = ⁻log₁₀[OH⁻]
Ca(OH)₂ → Ca²⁺ + 2OH⁻
1moldm⁻³ 1moldm⁻³ 2 x 1moldm⁻³
5 x 10⁻⁵moldm⁻³ 5 x 10⁻⁵moldm⁻³ 2( 5 x 10⁻⁵moldm⁻³ )
1 x 10⁻⁴moldm⁻³
Therefore;
pOH = -log₁₀ 1 x 10⁻⁴ = 4
Since
pOH + pH = 14
pH = 14 - 4 = 10
Since the planets absorbing more heat that would mean that the ice caps would melt drastically quicker and the Sea Levels Could Rise so D
A hypothesis is a "tentative proposition which is subject to verification through subsequent investigation....In many cases hypothese are hunches that the researcher has about the existence of relationships between variables." (Verma and Beard, 1981)
The hypothesis is the cornerstone of science, and hypotheses can be constructed and used in different ways.
In studies of complex, multi-factor systems (e.g., ecology and evolution), a hypothetico-deductive approach is often taken. On other areas, such as cellular and molecular biology, developmental biology, and other areas, hypotheses may be reached inductively, and a set of competing hypotheses potentially able to explain a given observed phenomenon may be tested and systematically eliminated until only the most likely explanations remain. To better understand each method, we should first review the differences between inductive and deductive reasoning.
Answer:
A chemical reaction is a rearrangement of atoms which turn one or more compounds into new compounds. Equations and models may describe all of the chemical reactions. ... If atoms detach from each other and recombine into various types of atoms, we conclude that there has been a chemical reaction.
5.7% KCl is 94.3 % water.
Therefore, for 1000 g of water the mass of KCl will be (1000× 5.7)/94.3 = 60.445 grams.
1 mole of KCl is equal to 74.55 g,
therefore, 60.445 g will be 60.445/74.55 = 0.8108 mole of KCl
Hence, 0.8108 moles of KCl should release twice that number of moles 1.6216 moles ions.
Having 1.6216 moles of KCl ions dissolved in 1000g of water, gives us 1.6216 molar if solution.
Using the freezing point depression constant of water.
dT = Kf (molarity)
dT = (1.86 C/ molar) (1.6216 m)
dT = 3.016 C drop in freezing point
Therefore, it should freeze at - 3.016 Celsius