Answer:
0.00230 = <u>3 significant figures</u>
Explanation:
Significant digits or figures of a given number are the digits or figures that have meaning and contributes to the precision of the given number.
Therefore, <u>0.00230 = 3 significant figures.</u>
Reason: The non-zeros figures and the trailing zero after the decimal are significant. Whereas, all the leading zeros are not considered significant.
genetics and reproduction is all about dna.
Answer:
The mole fraction of ethanol is 0.6. A 10 mL volumetric pipette must be used for to measure the 10 mL of ethanol. The vessel should be clean and purged.
Explanation:
For calculating mole fraction of ethanol, the amount of moles ethanol must be calculated. Using ethanol density (0.778 g/mL), 10 mL of ethanol equals to 7.89 g of ethanol and in turn 0.17 moles of ethanol. The same way for calculate the amount of water moles (ethanol density=0.997 g/mL). 2 mL of water correspond to 0.11. The total moles are: 0.17+0.11=0.28. Mole fraction alcohol is: 0.17/0.28=0.6
<u>Answer:</u> The mass of chlorine needed by the plant per day is 
<u>Explanation:</u>
We are given:
Volume o water treated per day = 25,000,000 gallons
Converting this volume from gallons to liters, we use the conversion factor:
1 gallon = 3.785 L
So, 
Amount of chlorine applied for disinfection = 10 mg/L
Applying unitary method:
For 1 L of water, the amount of chlorine applied is 10 mg
So, for 
of water, the amount of chlorine applied will be 
Hence, the mass of chlorine needed by the plant per day is
