Natural formation of lead occurs by radioactive decay of uranium and thorium through radon (222Rn). Four stable isotopes are known, 204Pb, 206Pb, 207Pb and 208Pb, the first three of which are used for estimating the ages of rocks. Lead compounds exist mainly in +2 or +4 oxidation states, the former being more common.
Answer:
1.95g of Mg(OH)2 are needed
Explanation:
Mg(OH)2 reacts with HCl as follows:
Mg(OH)2 + 2 HCl → MgCl2 + 2H2O
<em>Where 1 mole of Mg(OH)2 reacts with 2 moles of HCl</em>
To solve this question we must find the moles of acid. Then, with the chemical equation we can find the moles of Mg(OH)2 and its mass:
<em>Moles HCl:</em>
158mL = 0.158L * (0.106mol / L) = 0.01675 moles HCl
<em>Moles Mg(OH)2:</em>
0.01675 moles HCl * (2mol Mg(OH)2 / 1mol HCl) = 0.3350 moles Mg(OH)2
<em>Mass Mg(OH)2 -Molar mass: 58.3197g/mol-</em>
0.3350 moles Mg(OH)2 * (58.3197g / mol) =
<h3>1.95g of Mg(OH)2 are needed</h3>
Answer:
Your answer would be C.
Explanation:
Gamma radiation, unlike alpha or beta, does not consist of any particles, instead consisting of a photon of energy being emitted from an unstable nucleus. Having no mass or charge, gamma radiation can travel much farther through air than alpha or beta, losing (on average) half its energy for every 500 feet.
Answer:The equilibrium constant (kc) for the reaction 2HCl(g) =H2(g)+Cl2 (g) is 4×10^-34 at 25°C.
Explanation: