Explanation:in testing for oxygen a glowing splint is used.
the glowing splint is brought in the presence of the test tube containing the gas
the glowing splint rekindles or lights up showing that oxygen is present.
this is a positive test because oxygen supports burning or combustion
What we want to measure is the taste of coffee.
The following were kept constant during the experimental investigation:
The type of coffee,
The type of percolator,
The same amount and type of water,
The same perking time,
The same electrical sources.
Because these items were kept constant, they are not expected to influence the outcome of the experimental investigation.
Define:
y = the metric used to measure the taste of coffee
x = amount of coffee grounds used for the taste experiment.
Therefore the relationship that arises from the experiment is
y = y(x).
Because x is controllable and is varied during the experiment, it is the independent variable.
Because the measured value of y depends on x, therefore y is the dependent variable.
Answer:
The taste of coffee is the dependent variable.
The amount of coffee grounds used is the independent variable.
Answer:
Explanation:
Let the number of moles of oxygen = x
2H2 + O2 --> 2 H2O
x 13.3
Since the balance number for oxygen is 1 and the balance number for water is 2, you must set up a proportion. (Those balance numbers represent the number of moles).
1/x = 2 / 13.3 Cross Multiply
2*x = 13.3 Divide both sides by 2
2x/2 = 13.3/2
x = 6.65
You need 6.65 moles of oxygen.
The answer is Ra
Atomic number for Be is 4
Atomic number for Mg 12
Atomic number for Ra 88
Atomic number for Ba 56
