Answer:
The correct answer is "three groups of plants—a group fertilized by X, a group fertilized by Y, and a control group with no fertilizer".
Explanation:
I had to look for the problem to know the options.
The best way to determine which fertilizer is most effective is to have three evaluation groups. One group will be tested with fertilizer X and another with fertilizer Y. By leaving the third group without applying fertilizer, this will be the general pattern for comparing the effectiveness of the other two.
Have a nice day!
Answer:
If it loses 2 electrons, the net charge on the atom will be 2+
If the atom instead gains 4 electrons, the net charge will be 4-
Explanation:
It is based on adding and subtracting charges. Protons are +1 and electrons are -1
If the atom has 9 protons and 9 electrons, the net charge is +9 + (-9) = 0. The +9 is the 9 protons and the -9 is from the 9 electrons.
If two electrons are taken away, there would be 9-2 or 7 electrons with 9 protons. The net charge would then be +9 + (-7) = +2. +9 comes from the 9 electrons and -7 is from the 7 electrons.
So, if two electrons are taken away, the net charge is +2.
Similarly, if the atom gains 4 electrons, there will be 9+4 or 12 electrons and 9 protons. The net charge would then be +9 + (-12) = -4. +9 comes from the 9 protons and -12 comes from the 12 electrons.
So, if 4 electrons are added, the net charge is -4.
Answer:
10.8 ml
Explanation:
The BOD is an empirical test to determine the molecular oxygen used during a specified incubation period (usually five days), for the biochemical degradation of organic matter (carbonaceous demand) and the oxygen used to oxidise inorganic matter.
See attached file
Answer: The correct option is 2.
Explanation: Polyatomic ions are defined as the ions in which two or more elements are covalently bonded to act as a single unit. They always carry some charge.
Examples of polyatomic ions are: 
known as hydroxide ion, 
known as sulfate ion
We are given a compound 
having 2 ions which are 
and 
. these ions are named as sodium ions and hydrogen carbonate ions.
Therefore, the correct option is 2.
Answer:
V₂ = 568.9 mL
Explanation:
Given data:
Volume of gas = 550 mL
Pressure of a gas = 960 mmHg
Temperature = 200.0°C ( 200+273 = 473 K)
Final volume = ?
Final pressure = 830 mmHg
Final temperature = 150°C (150+273 = 423 K)
Solution:
Formula:
P₁V₁/T₁ = P₂V₂/T₂
P₁ = Initial pressure
V₁ = Initial volume
T₁ = Initial temperature
P₂ = Final pressure
V₂ = Final volume
T₂ = Final temperature
Solution:
V₂ = P₁V₁ T₂/ T₁ P₂
V₂ = 960 mmHg × 550 mL × 423 K / 473 K ×830 mmHg
V₂ = 223344000 mL / 392590
V₂ = 568.9 mL
