The much of the sample that would remain unchanged after 140 seconds is 2.813 g
Explanation
Half life is time taken for the quantity to reduce to half its original value.
if the half life for Scandium is 35 sec, then the number of half life in 140 seconds
=140 sec/ 35 s = 4 half life
Therefore 45 g after first half life = 45 x1/2 =22.5 g
22.5 g after second half life = 22.5 x 1/2 =11.25 g
11.25 g after third half life = 11.25 x 1/2 = 5.625 g
5.625 after fourth half life = 5.625 x 1/2 = 2.813
therefore 2.813 g of Scandium 47 remains unchanged.
Answer:
Sorry for the lack of precision, if you have any questions you can consult me again.
Explanation:
Glycine is an amino acid, forms proteins and is also called in its molecular chemical formula as C2H5NO2
Answer:
25% gold.
Explanation:
6 is 25 percent of 24, so 6 karat gold would be 25% gold.
Answer is: no reaction occurs, because all salts are soluble in water.
Balanced chemical reaction:
Zn(NO₃)₂(aq) + MgSO₄(aq)→ Mg(NO₃)₂(aq) + ZnSO₄(aq).
Ionic reaction:
Zn²⁺(aq) + 2NO₃⁻(aq) + Mg²⁺(aq) + SO₄²⁻(aq) → Mg²⁺(aq) + 2NO₃⁻(aq) + Zn²⁺ + SO₄²⁻(aq).
This chemical reaction is double displacement reaction - cations and anions of the two reactants switch places and form two new compounds.