First the environment must be appropriate - corrosion, top temperature, etc.
Some thermo couples are required to have a linear input-output function.
The sensitivity of the couple has to be appropriate - a useful output.
There are tables listing the properties of various couples.
Criterion is the singular form of criteria.
The plural form of criterion is criteria.
The plural form of the noun "criterion" is "criteria."
The plural form of criterion is criteria.
Criteria is plural
Metals are usually positive and non-metals are usually negative.
The singular form of "criteria" is "criterion." So, "criterion is" would be proper, as would "criteria are." "Criteria is" or "criterion are" would not.
All metals can form chemical compounds.
The word 'criteria' is the plural form of the singular word 'criterion'. 'Those are the criteria that I used in making my decision.' 'That is the criterion that I used in making my decision.' It is wrong to use the word 'criteria' as a singular. Similarly, it is wrong to use 'phenomena' as a singular. It is the plural form of the singular word 'phenomenon'.
Criteria is plural. Criterion is singular. The criteria to pass a maths exam is being able to add up and subtract. The criterion of passing an addition exam is being able to add up.
metals were moulded to form objects in a blacksmith shop by heating metals or by pressing it to form different shapes.
Metals and nonmetals form ionic bonds.