Answer:
science ka Hindi kya hoga
Answer:
D. 0.75 grams
Explanation:
The data given on the iridium 182 are;
The half life of the iridium 182,
= 15 years
The mass of the sample of iridium, N₀ = 3 grams
The amount left, N(t) after two half lives is given as follows;

For two half lives, t = 2 × 
∴ t = 2 × 15 = 30


∴ The amount left, N(t) = 0.75 grams
Sodium reacts with water to form a colorless solution of sodium hydroxide and hydrogen gas.
Answer:
2Fe + 3H2SO4 + Fe2(SO4)3+ 3H2
Explanation:
1. Fe (SO4) 3 is an incorrectly written formula because iron is trivalent as we can see by this three ahead of SO4. SO4 is divalent always.
2. since (SO4) is 3, this three shows us that there must be 3 in the reactants as well.
so now there is 3H2SO4
3. Since we have added 3 to one hydrogen we must add another. So now it's 3H2
4. and finally iron. In Fe2 (SO4) 3 we see this 2 in front of Fe which means it goes 2Fe.
Answer:
This exemplifies the agricultural role of water.
Explanation: