I had the same question, it's most likely B.
Answer:
answer:-
a long-term increase in the Earth's average temperature
Answer:
An experiment is a research method performed within a completely controlled environment that uses groups of individuals ( subjects), one of which the factors being tested are not spplied on, an independent factor of the hypothesys ( to be tested ), for example the resilience of a group of teenagers) and a dependant factor that is applied to check how it varyes depending on the tested factor ( for example, the most challanging experience of their generation)
Answer:
0.156mol
Explanation:
Number of moles of a substance can be calculated from its mass by dividing its mass by molar mass i.e.
Number of moles (n) = mass/molar mass
Molar mass of PbCl4 is as follows, where Pb = 207.2g/mol, Cl = 35.5g/lol
PbCl4 = 207.2 + 35.5(4)
= 207.2 + 142
= 349.2g/mol
Using: mole = mass/molar mass
mole = 54.32 grams ÷ 349.2g/mol
mole = 0.1555
mole = 0.156mol
Same number of valence electrons
Explanation:
Two elements posses similar chemical properties if they have the same number of valence electrons.
Chemical properties of any substance is determined by the number of valence electrons it possesses in its outer most shell.
Elements use their valence electrons to form chemical bonds with one another.
Elements with the same number of valence electrons will chemically combine the same way.
This is why elements in the same group on the periodic table have the same chemical properties.
learn more:
Chemical properties brainly.com/question/2376134
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