<u>Answer:</u> The molarity of saline solution is 0.909 M
<u>Explanation:</u>
We are given:
5.21 w/w % NaCl
This means that 5.21 grams of NaCl is present in 100 grams of solution
To calculate mass of a substance, we use the equation:
Density of solution = 1.02 g/mL
Mass of solution = 100 g
Putting values in above equation, we get:
To calculate the moalrity of solution, we use the equation:
Given mass of NaCl = 5.21 g
Molar mass of NaCl = 58.44 g/mol
Volume of solution = 98.04 mL
Putting values in above equation, we get:
Hence, the molarity of saline solution is 0.909 M
Answer:
According to mass and volume, block density is 2 g/ml
Explanation:
Density is a measure, usually used in physics and chemistry, that relates the mass and volume of a solid or compound.
In general terms, the density is directly proportional to the mass, and inversely proportional to the volume, so increasing the mass will also increase the density.
The formula used to calculate the density is
ρ = 
Therefore, according to the mass and density of the block
ρ = 
= 2g/ml
Being the density of the block equal to 2 g/ml.
<em>The other options are not possible, because the values given do not correspond to the result of the equation.</em>
Answer:
Explanation:
Shifting, labor intensive and monoculture are different in terms of description,restrictions and problem.
Shifting is an agriculture method in which an area if land is cultivated for a while and abandoned for the soil to regain and preserve it's fertility. It is done to restore soul fertility.
It has restrictions because it is done in places where there is large areas of land, if there is not large area of land, it will be done.
It can lead to defforestation because trees are cut fine for land cultivation and after a while the land is abandoned and trees are cut down some where else too.
Labor intensive refers to agricultural industry requiring or needing large amount of labor to produce agricultural products. Labor intensive is restricted to areas where there is low or no people who can engage in agricultural services.
Labor intensive require high skilled people which might not be available.
Monoculture is a farming system where by a single crop is cultivated in an area of land.
The problem of monoculture is that it displaces species and nutrients occuring naturally in an ecosystem.
Monoculture is restricted in areas where diversity of crops are needed.
Answer:
Explanation:
<u>1) Data:</u>
a) [OH⁻] = 2.1 × 10⁻⁶ M . . . (the symbol g shown in the question is a typo)
b) pH = ?
<u>2) Formulae:</u>
<u>3) Solution:</u>
- pOH = log ( 1 / 2.1 × 10⁻⁶ ) = 5.7
- pH = 14 - pOH = 14 - 5.7 = 8.3
You are looking for an element in the fourth period and a transition metal. As most have about 3 valence electrons. Gallium and Scandium work perfectly.
