You can reduce wind erosion by providing a protective plant cover for the soil.
Answer:
True
Explanation:
Fossil age can determine organism changes related to the time scale. Fossils provide scientists with evidence that allows them to hypothesize how living organisms have evolved over time.
fossil can be studied to determine what kind of organism it represents, how the organism lived, and how it was preserved. However, by itself a fossil has little meaning unless it is placed within some context. The age of the fossil must be determined so it can be compared to other fossil species from the same time period. Understanding the ages of related fossil species helps scientists piece together the evolutionary history of a group of organisms.
Answer:
6.53g of K₂SO₄
Explanation:
Formula of the compound is K₂SO₄
Given parameters:
Volume of K₂SO₄ = 250mL = 250 x 10⁻³L
= 0.25L
Concentration of K₂SO₄ = 0.15M or 0. 15mol/L
Unknown:
Mass of K₂SO₄ =?
Methods:
We use the mole concept to solve this kind of problem.
>>First, we find the number of moles using the expression below:
Number of moles= concentration x volume
Solving for number of moles:
Number of moles = 0.25 x 01.5
= 0.0375mole
>>Secondly, we use the number of moles to find the mass of K₂SO₄ needed. This can be obtained using the expression below:
Mass(g) = number of moles x molar mass
Solving:
To find the molar mass of K₂SO₄, we must know the atomic mass of each element in the compound. This can be obtained using the periodic table.
For:
K = 39g
S = 32g
O = 16g
Molar mass of K₂SO₄ = (39x2) + 32 + (16x4)
= 78 +32 + 64
= 174g/mol
Using the expression:
Mass(g) = number of moles x molar mass
Mass of K₂SO₄ = 0.0375 x 174 = 6.53g
<span>Total mass = 3.64 + 2.87 + 4.13 = 10.64 g
Mass percent of NH4Cl = (mass of NH4Cl/ Total mass) x 100 = (2.87 g/10.64g) x 100 = 27.0 % mass of NH4Cl</span>
Explanation:
Which molecule does not obey the Octate rule of valence electrons .
BeCl2
FeCl2
CuCl2
ZnCl2
→BeCl2
Explaination:
BeCl2 violates the octet rule because the boron should be in a suitable valence state such that it binds to 3 chlorines. However, in this molecule boron is associated with six electrons.
