The answer is starch because iodine reacts with starch to change the colour to inky blue or black.
All the others are present in milk naturally so I’m assuming they intent starch
<span>Answer : The average atomic mass of rubidium = 85.468
Explanation: Given that 85Rb isotope has atomic mass of 84.912amu with abundance of 72.17%
therefore we get 84.912 x 0.7217 = 61.281
and 87Rb isotope has atomic mass of 86.909 with abundance of 27.83%
hence we get 86.909 x 0.2783 = 24.187
Thus we get 61.281 + 24.187 = 85.468 as the average atomic mass of Rubidium.</span>
Answer: Question 8) 0.45 mole NaCl
Question 9) 1.7 moles Fe2+
Question 10) 9.52 moles Fe2+
Explanation: solution attached
The reaction will be: FeBr2 + K --> KBr + Fe
Balancing gives: FeBr2 + 2K --> 2KBr + Fe
The molar mass of FeBr2 is 55.85 + 2*79.9 = 215.65 g/mol.
We divide 40 g / 215.65 g/mol = 0.185 mol FeBr2
Based on stoichiometry:
(0.185 mol FeBr2)(2 mol KBr/1 mol FeBr2) = 0.370 mol KBr
Answer:
Iron metal is more reactive than copper.
Explanation:
Iron metal is more reactive than copper. ... Cu is less reactive than iron, therefore, cannot replace iron from iron sulphate (FeSO4). we have already seen that iron is more reactive than copper. So that means that in this reaction, copper is less reactive than iron. That means copper cannot displace iron. It cannot kick out iron from a sulfate.
