Answer:
Explanation:Metalloids may act either like metals or nonmetals in chemical reactions. Most metalloids have some physical properties of metals and some physical properties of nonmetals. They fall between metals and nonmetals in their ability to conduct heat and electricity. They are shiny like metals but brittle like nonmetals.
Mass number is the total number of protons and neutrons and atomic number is the number of neutrons.
So you just subtract
Mass number - atomic number = neutrons
(Prot + neut) (Protons)
Answer: yellow
When you mix solutions of lead (II) nitrate and potassium iodide. The precipitate is yellow in colour and the compound is lead (II) Iodide. Pb (NO3)2(aq) + 2KI(aq) → PbI2(s) + 2KNO3(aq). Yes, it is a double displacement reaction.
Explanation: The lead nitrate solution contains particles (ions) of lead, and the potassium iodide solution contains particles of iodide. When the solutions mix, the lead particles and iodide particles combine and create two new compounds, a yellow solid called lead iodide and a white solid called potassium nitrate. When a solution of potassium iodide is added to a solution of lead nitrate taken in a test tube, the precipitation of a yellowish solid is observed. This yellowish solid is lead iodide. Potassium nitrate is formed along with lead iodide. When lead nitrate is mix with potassium iodine, a precipitation reaction occurs and yellow precipitate of lead iodide is formed.
Answer:
75.2 degree Fahrenheit was the predicted high temperature.
Explanation:
Predicted high temperature in the Spain = T' = 24°C
In Spain temperatures are measured in Celsius. But we have to calculate the temperature in Fahrenheit .
To convert this temperature into Fahrenheit, we use the conversion factor:
75.2 degree Fahrenheit was the predicted high temperature.
Explanation:
a) Anode:
Cathode :
b)
c) As , the reaction is spontaneous.
d)
Explanation:
a) Here Ni undergoes oxidation by loss of electrons, thus act as anode. Hydrogen undergoes reduction by gain of electrons and thus act as cathode.
Anode:
Cathode :
b) The representation is given by writing the anode on left hand side followed by its ion with its molar concentration. It is followed by a slat bridge. Then the cathodic ion with its molar concentration is written and then the cathode.
c)
Where both are standard reduction potentials.
= +ve, reaction is spontaneous
= -ve, reaction is non spontaneous
= 0, reaction is in equilibrium
Thus as , the reaction is spontaneous.
d) The standard emf of a cell is related to Gibbs free energy by following relation:
= standard gibbs free energy
n= no of electrons gained or lost
F= faraday's constant
= standard emf
Thus value of Gibbs free energy is -48250 Joules.