Answer:
Please find the explained difference below
Explanation:
In a scientific experiment, the CONTROLLED VARIABLE, also known as CONSTANT, is the the variable that is kept unchanged by the experimenter throughout the course of the experiment. The constants are not part of the actual experiment but altering them can influence its outcome.
A control group is one of the two groups in an experiment (the other being experimental group) that doesn't receive the variable being manipulated (independent variable). The control group is the same as the experimental group except that the independent variable is unchanged in the control group. It is used to make a comparison with the experimental group.
For example, in an experiment to test the effect of sunlight on plant growth. Some plants were exposed to sunlight while some were placed in the dark. The CONTROL group of this experiment are the plants placed in the dark (no light). They didn't receive any treatment.
The constants of this experiment can be same amount of water, same type of plants used etc. This is done in order not to affect the outcome of the experiment.
Answer:
Ecology is the study of how organisms interact with one another and with their physical environment.
Explanation:
<u>Given data:</u>
Volume of solution measured = 0.0067 L
<u>To determine:</u>
The number of significant figures
<u>Explanation:</u>
Significant figures are the number of digits that accurately describe a measured value.
As per the rules:
All non-zero digits are significant
Leading zero's i.e. the zero's after a decimal which comes before a non-zero digit are not significant
Hence in the given value 0.0067, there are 2 significant figures (6 &7)
Answer:
42.65g
Explanation:
Given parameters:
Mass of K = 4g
Unknown: Mass of KCl
Solution:
Complete equation of the reaction:
2K + Cl₂ → 2KCl
To solve this problem, we know that the reactant in short supply is potassium K and this dictates the amount of products that would be formed. The chlorine gas is in excess and we can't use it to determine the amount of product that would form.
Now, we work from the known to the unknown. Since we know the mass of K given in the reaction, we can simply find the molar relationship between the reacting potassium and the product. We simply convert the mass to mole and compare to the product. From there we can find the mass of KCl that would be produced.
Calculating number of moles of K
Number of moles = 
Number of moles of K = 
= 0.103mol
From the given reaction equation:
2 moles of K will produce 2 moles of KCl
Therefore 0.103mol of K will produce 0.103mol of KCl
To find the mass of KCl produced,
Mass of KCl = number of moles of KCl x molar mass
Molar mass of KCl = 39 + 35.5 = 74.5gmol⁻¹
Mass of KCl = 0.103 x 74.5 = 42.65g
