Answer:
116 years
Explanation:
To solve this, we will use the half life equation;
A(t) = A_o(½)^(t/t_½)
Where;
A(t) is the amount of strontium left after t years;
A_o is the initial quantity of strontium that will undergo decay;
t_½ is the half-life of strontium
t is the time it will take to decay
We are given;
A(t) = 7.5 g
A_o = 120 g
From online values, half life of strontium-90 is 29 years. Thus, t_½ = 29
Thus;
7.5 = 120 × ½^(t/29)
Divide both sides by 120 to get;
7.5/120 = ½^(t/29)
0.0625 = ½^(t/29)
In 0.0625 = (t/29) In ½
-2.772589 = (t/29) × (-0.693147)
(t/29) = -2.772589/(-0.693147)
t/29 = 4
t = 29 × 4
t = 116 years
Answer:
<em><u>A solid has a definite shape and volume.</u></em>
<em><u>A solid has a definite shape and volume.Solids in general have higher density.</u></em>
<em><u>A solid has a definite shape and volume.Solids in general have higher density.In solids, intermolecular forces are strong.</u></em>
<em><u>A solid has a definite shape and volume.Solids in general have higher density.In solids, intermolecular forces are strong.Solids have high melting points.</u></em>
sedimentary. almost all fossils are found in sedimentary rocks
solution;
Rhizoferrin is a member of a new class of siderophores (microbial iron transport compounds) based on carboxylate and hydroxy donor groups rather than the commonly encountered hydroxamates and catecholates. We have studied the coordination chemistry of rhizoferrin (Rf), as a representative of this group, with Fe(3+), Rh(3+), Cr(3+), Al(3+), Ga(3+), VO(2+), and Cu(2+). The metal complexes have been studied by UV-vis, CD, NMR, and EPR spectroscopies and mass spectrometry. The formation constants for the iron complex have also been measured and yield a log K(LFe) of 25.3. The Rh and Cr rhizoferrin complexes are unusual in that they appear to adopt a chirality about the metal center that is the opposite of the native iron analog. Several of the alternative metal ion complexes are found to have biological activity toward Morganella morganii in a plate type assay.
I believe it occurs along the plates edge.
