Answer:
MIXTURE
Explanation:
A mixture is a substance composed of a combination of other different substances. These component(s) of a mixture are physically combined, meaning that there is no chemical linkage between the individual components/constituents of a mixture.
This is the case of the gravel described in this question. The components of gravel can be separated using physical means because they are not chemically bonded to one another, hence, no chemical reactions are needed to separate different parts of gravel into pure substances. This makes gravel a MIXTURE.
Answer:
These organelles are like the organs in a human and they help the cell stay alive. Each organelle has it's own specific function to help the cell survive. The nucleus of a eukaryotic cell directs the cell's activities and stores DNA. ... All of the cell's organelles must work together to keep the cell healthy.
Explanation:
These organelles are like the organs in a human and they help the cell stay alive. Each organelle has it's own specific function to help the cell survive. The nucleus of a eukaryotic cell directs the cell's activities and stores DNA. ... All of the cell's organelles must work together to keep the cell healthy.
<u>Answer:</u> The result of the given calculation is 
<u>Explanation:</u>
Scientific notation is defined as the notation in which a number is expressed in the decimal form. This means that the number is always written in the power of 10 form.
We are given an expression:
The operation carried out in the above expression is division operation. The units are also treated in the same way.
The solution for the above expression is:
The value in scientific notation is
Hence, the result of the given calculation is
Answer:
Alkaline earth metals
Explanation:
Calcium (Ca) is a silvery-white soft metal that has the atomic number 20 in the periodic table. It is an Alkaline Earth Metal and is located in Group 2 of the periodic table. It has the symbol Ca.
Solution:
We have to use the Henderson-Hasselbalch equation: for this calculation
Henderson–Hasselbalch equation describes the derivation of pH as a measure of acidity by using pKa, the negative log of the acid dissociation constant in biological and chemical systems. The equation is also useful for estimating the pH of a buffer solution and finding the equilibrium pH in acid-base reaction.
The equation is given by:
Here, [HA] is the molar concentration of the un dissociated weak acid, [A⁻] is the molar concentration (molarity, M) of this acid's conjugate base and pKa is −log10 Ka where Ka is the acid dissociation constant, that is:
pH = pKa + log([A^-]/[HA])
We look up the pKa for acetic acid:
pKa = 4.76
Let x = molarity of AcO^- and y = molarity of AcOH: Then we have the following two equations in two unknowns:
(1) x + y = 0.10 M
and
(2) 4.9 = 4.76 + log(x/y)
Further calcite the value of x and y by algebraic method and get the answer.
