Explanation:
When we are using spoon, beaker, stirring rod and graduated cylinder then they directly come in contact with the chemical we are using. Hence, if they are not washed thoroughly then chemicals remain deposited over them.
As a result, when successive test are performed using the same contaminated apparatuses then we do not get the desired results.
Whereas distilled water in a spray bottle if poured without touching or coming in contact with any kind of chemicals.
Hence, we can conclude that spoon, beaker, stirring rod and graduated cylinder are the tools that could have become cross-contaminated during the experiment if you had not cleaned them carefully between successive tests.
Answer:The n = 3 shell, for example, contains three subshells: the 3s, 3p, and 3d orbitals. There is only one orbital in the n = 1 shell because there is only one way in which a sphere can be oriented in space.
Explanation:hope this helps:D
Answer:

Given:
- Given mass of NaOH = 30 gram
- Molar mass of NaOH = 40 gram
- Volume = 2.40 litres
To find:
Molarity = ?
Solution:
<em>Molarity is nothing but the number of moles of solute dissolved in per litre of solution. given by </em><em>formula,</em>



Answer:
The absolute pressure inside the ball is 1.25atm.
Explanation:
Given-
Volume, V = 5..27L
Temperature, T = 27°C
Gauge Pressure, Pg = 0.25 atm
Atmospheric pressure, Patm = 1 atm
Absolute pressure, Pabs = ?
We know,
Therefore, absolute pressure inside the ball is 1.25atm.