The correct answer is A. A test tube of zinc oxide. Zinc oxide is a compound which is a pure substance composed of two or more elements. They can only be separated or broken down into its individual elements or smaller compounds by chemical means. Therefore, the answer is a test tube of zinc oxide.
<span>The answer is the first option. Enzyme and substrate bind using a lock-and-key mechanism. Enzymes act on a specific substrate and a substrate needs a specific enzyme, this is what is called a lock-and-key mechanism. Enzymes and substtates are like a key and a lock, one is for each other.</span>
Polarity is a term used in electricity, magnetism, and electronic signaling. Suppose there is a constant voltage , also called an electric potential or electromotive force (EMF), between two objects or points. In such a situation, one of the objects or points (poles) has more electrons than the other.
<h3>What causes electrical polarity?</h3>
This happens when the hot and neutral wires get flipped around at an outlet, or upstream from an outlet. Reversed polarity creates a potential shock hazard, but it's usually an easy repair.
<h3>Why is electrical polarity important?</h3>
When working with electrical circuits, we often refer to the polarity between different points in the circuit. Understanding polarity is important for connecting the leads of polarity-dependent devices such as some meters and motors. Polarity is also important for determining the direction of current flow.
Learn more about polarity here:
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The volume of ideal gas that would occupy at 1.50 atm and 216 c is
2016.49 ml
<u><em>calculation</em></u>
- volume is calculated using a combined gas equation
that is P1V1/T1= P2V2/T2
P1( pressure 1) = 7.20 atm
V1 ( volume 1) = 250 ml
T1 ( temperature 1) = 18 + 273=291 K
P2 ( pressure 2) = 1.50 atm
T2 ( temperature 2)= 216+273=489 K
V2 ( volume 2) =?
- by making V2 the subject of the formula
V2=[(T2 xP1 x V1)/(T1 xP2)]
V2=[ (489 K x 7.20 atm x 250 ml) / ( 291 k x 1.50 atm)] = 2016.49 Ml
The collection of elements on the right side of the periodic table with electron sequetianlly filling the p orbitals of their valence shells are named noble gases.
The noble gases are in the group 18.
The last orbital of the noble gases are:
Gas last orbital
He 1s
Ne 2p6
Ar 3p6
Kr 4p6
Xe 5p6
Rn 6p6
As you see the p orbitals of the noble gases are complete. That is what confere them their great stability.
