The answer is B. uniform in composition.
Answer:
1. Fe + H2SO4 = FeSO4 + H2
iron + sulfuric acid = duretter + hydrogen
2. Mg + 2 HNO3 = Mg(NO3)2 + H2
Magnesium + nitric acid = magnesium nitrate +hydrogen
3. Zn + 2 HCl = ZnCl2 + H2
Zinc + hydrogen chloride= zinc chloride+ hydrogen
To evaluate the accuracy of a measurement, the measured value must be compared to the correct value. To evaluate the precision of a measurement, you must compare the values of two or more repeated measurements.