The letter (d.) strong base or acid would be the most appropriate answer to the question above. An indicator is a strong base or acid. Indicators are strong base and acid because through this you can determine if a compound is acid or base with its color.
Answer: 0.00867 moldm-3
Explanation:
Since the reaction is 1st order,
Rate of reaction=∆[A]÷t
0.646-0.0146/72.8= 0.00867
Remember that in a first order reaction, the rate of reaction depends on change in the concentration of only one of the reaction species, A in the problem above.
Answer to the Question
C. Barium phosphate
Hi!
To make 500 mL of a 1,500 M solution of NaCl you'll require
43,83 g
To calculate that, you will need to use a conversion factor to go from the volume of the 1,500 M solution to the required grams. For this conversion factor, you'll use the definition for Molar concentration (M=mol/L) and the molar mass of NaCl. The conversion factor is shown below:

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