Answer:
CO is the chemical formula for carbon monoxide.
Co is the chemical symbol for cobalt.
W is the chemical symbol for tungsten.
Be is the chemical symbol for beryllium.
HI is the chemical formula for hydrogen iodide.
Explanation:
Chemical symbols are either written as a single uppercase letter (ex. O) or an uppercase letter and a lowercase letter (ex. Na).
Chemicals can be anything else! For example CO or even somthing like LiIO.
Answer:
Explanation:
Efficiency of the electric power plant is 
Here Temperature of hot source 
and Temperature of sink 
Hence the efficiency is
Now another formula for thermal efficiency Is

Here QI is the of heat taken from source 100 MJ ; Q2 of heat transferred to the sink (river) to be found
W is the of work done and W = QI -Q2
Hence From

Hence the of heat transferred to the river Is 
Option (a) is correct.
A reducing agent is the one which loses electrons to other substance.
Here, Zn has oxidation number 0 in the L.H.S of the equation, but on R.H.S its oxidation number is +2 i.e. it Zn has donated two of its electrons to

.
Hence, Zn is the reducing agent here.
Salinity has units of grams NaCl or salt per kilogram solution. We can use the density given and the molar mass of the salt to convert from salinity to molarity. We do as follows:
( 5.6 g / kg ) ( 1.03 kg / L ) ( 1 mol / 58.44 g ) = 0.0987 mol NaCl / L
Answer:
a, b, c, d
Explanation:
Rutherford’ atomic model is based on the gold foil experiment. In this experiment, beam of alpha rays was bombarded on thin gold foil. He observed that:
Most of the alpha particles passed through thin foil without any deflection.
Few alpha particles deflected by an angle of 90o.
Based on observation, Rutherford concluded that majority of the space inside the atom is empty.
He explained defection of few alpha particles by assuming that most of the mass is concentrated at the nucleus and positively charged.
Therefore, among given, the correct statements are:
The atom contains a positively charged nucleus.
Positive charge is condensed in one location within the atom.
The majority of the space inside the atom is empty space
The mass of an atom is concentrated at the nucleus
Therefore, the correct options are:
a, b, c, d