The reaction equation may be written as:
2Li + 2H₂O → 2LiOH + H₂
A single mole of gas occupies 22,400 ml of gas at STP. Therefore, the moles of hydrogen gas are
75.5 / 22,400 = 0.0034 mol
According to the equation, the moles of lithium are twice that of hydrogen gas; thus,
0.0034 x 2 = 0.0068 mol
The mass of lithium is given by:
mass = moles x atomic mass
mass = 0.0068 x 6.9
mass = 0.047 grams
Answer:
Therefore, when an atom becomes a positive ion is pulls its electrons closer, decreasing is radius moreover, when it becomes a negative ion, it pulls its electrons closer and decreases the radius.
Answer:
The two valid principles are:
- Scientific theories can be replaced by better theories.
- An experiment can disprove a theory that scientists have accepted.
Explanation:
The scientific knwoledge is not inmutable; it may (and does) change with new discoveries.
In fact, scientific theories cannot be proved right, instead they are constantly tested to try to disprove them. This is what the principle that theories are falsiable means.
As long as a scientific theory is not disproved it remains valid, but new discoveries may lead, eventually, to its disprovement.
Scientific knowledge evolves because new procedures, new technologies, and new evidence leads to a better understanding and better explanations.
