<span>I didn't know Selenium was considered organic? :P atoms form ions that mimic the electronic structure of noble gases. so add or subtract electrons from the atom to achieve the configuration of a noble gas.</span>
Answer:
1. Lanthanum-139 atom is the stable isotope of lanthanum with relative atomic mass 138.906348, 99.9 atom percent natural abundance and nuclear spin 7/2.
2. In fact, over 80% of electric cars sold globally utilized permanent magnet-based motors in 2019. These magnets are typically made with rare-earth materials such as neodymium and dysprosium, which have a very geographically constrained supply chain.
3. It is the second most reactive of the rare-earth metals after europium. Lanthanum oxidizes in air at room temperature to form La2O3. It slowly reacts with water and quickly dissolves in diluted acids, except hydrofluoric acid (HF) because of formation of a protective fluoride (LaF3) layer on the surface of the metal.
Explanation:
Magnesium is classified as a metal. Magnesium has two valence electrons
The question in English is "<span>Determine the mass, in kg, of a material that is contained in a volume of 18L. It is known that the material density is 0.9 g/cm 3"
Answer:
</span>
We can use a simple
equation to solve this problem. <span>
d =
m/v</span><span>
<span>Where </span>d <span>is
the density, </span>m <span>is
the mass and </span>v is the volume.
d = </span>0.9<span> g/cm³
m = ?
v = </span>18 L = 18 x 10³ cm³<span>
By applying the equation,
<span> 0.9 g/cm³ = m / </span></span>18 x 10³ cm³<span>
m = 0.9 g/cm³ x </span>18 x 10³ cm³<span>
<span>
</span>m = 16200 g
m = 16.2 kg
Hence, the mass of
18 L of material is 16.2 kg.</span>
AgNO3(aq) + KCl (aq)-----> AgCl(s) + KNO3(aq)
Ag ^+(aq) + NO3^-(aq) + K^+ (aq) + cl^- (aq) ----> AgCl(s) + K^+(aq) + NO3^-(aq)
net ionic equation
Ag ^+(aq) + Cl^-(aq) ----> AgCl(s)