The purpose of the uninoculated control tubes used in this test is that two uninoculated control tubes are needed to show the results of the medium in both aerobic and anaerobic environments. It is used to show it is sterile and also as a color comparison, used also to show that the medium remains green under both conditions.
In easy words the connection between Reactants, Products and Limiting reactants is as follow,
Reactants and Products:
Reactants are the starting materials for the synthesis of final synthesized materials called as products.
Example:
CH₄ + 2 O₂ → CO₂ + 2 H₂O
In above reaction Methane (CH₄) and Oxygen (O₂) are the reactants while, CO₂ and H₂O are the products.
Reactants, Products and Limiting Reactants:
Considering the same example it is seen that for one mole of CO₂ two moles of O₂ are required to completely convert into CO₂ and H₂O. If either of the reactant is taken less than the required amount then it will act as a limiting reactant because it will consume first leaving the second reactant present in excess as compare to it. Hence, we can say that the limiting reactant is the starting material which controls the amount of product being formed.
<u>Answer 2 :</u> The given electronic configuration for a neutral atom of phosphorous in its ground state is incorrect.
Explanation :
A neutral atom of phosphorous has 15 electrons.
The given electronic configuration is incorrect.
The reason is, According to Aufbau principle, the electrons will be first filled in the sub-shell having lower orbital energy. As from the given configuration, 3p sub-shell has lower orbital energy than 4s sub-shell. So, the electrons will be filled in 3p sub-shell first. Hence, the ground state electronic configuration of neutral atom of phosphorous is,
<u>Answer 3 :</u>
Element Rubidium Magnesium Aluminium
Symbol Rb Mg Al
Group number 1 2 13
Number of valence 1 2 3
electrons
The order of general reactivity on the basis of number of valence electrons.
Rb > Mg > Al
Reason : The reactivity is determined by the number of electrons present in the outermost shell that means the element which have 1 valence electron will be more reactive because they can easily lose electrons.
Between phosphorous, sulfur, chlorine and argon, argon is the element that's the least likely to form an ionic bond with sodium.
Answer:
O, S, Te
Cl, Br, Se
Explanation:
Main group elements have an electronegativity that increases across a period (from left to right) and decreases down a group.
Each atom has its own value which you can find on the electronegativity chart.
Metals have low values
Nonmetals have high values
I'm your case:
O = 3.5
S = 2.5
Te = 2.1
Cl = 3.0
Br = 2.8
Se = 2.4
