D. powder residues.
the police and forensic chemists usually perform a qualitative test called GPR or gun powder residue. the residue sticks to the skin.
An ion is a charged atom or molecule. It is charged because the number of electrons do not equal the number of protons in the atom or molecule. An atom can acquire a positive charge or a negative charge depending on whether the number of electrons in an atom is greater or less then the number of protons in the atom. An example is Iron (III) , Iron (II) , lithium, and hydrogen.
This is false, because copper is an element.
To be solution, it has to have at least 2 different substances. Solid solution of metals is often called alloy.
Answer:
<h2>10 m/s</h2>
Explanation:
Her average speed can be found by using the formula

d is the distance
t is the time taken
From the question we have

We have the final answer as
<h3>10 m/s</h3>
Hope this helps you
First step: convert 22.4% into fraction
that is 22.4/100 which is equivalent to 0.224
The mass of Cucl2 contained in 75.85 of 22.4% by mass of solution of CUcl2 in water is therefore,
0.224 x75.85=16.99g
alternatively
75.85 --->100%
? 22.4%
by cross multiplication =(22.4 x 75.85)/100 =16.99g