Sorry, I'm late, but the answers are:
Metals are malleable
Metals are ductile
Metals ARE good heat and electricity conductors
Metals lose electrons in reactions
Volume of a cylinder: V= pi (r)^2(h)
The percent by mass : 6.3%
<h3>Further explanation</h3>
The concentration of a substance can be expressed in several quantities such as moles, percent (%) weight/volume,), molarity, molality, parts per million (ppm) or mole fraction. The concentration shows the amount of solute in a unit of the amount of solvent.
mass of potassium nitrate = 8.4 g⇒solute
- mass of solution = mass of solute+mass of solvent(water)
mass of potassium nitrate + mass of water = 8.4 g + 125 g =133.4 g
Percent by mass of the solute :
Half life is defined as the amount of time it takes for a radioactive material to divide itself into half after radioactive decay process. So basically, after the prescribed half-life, what transforms to another material is 1/2 of the original and what is left is 1/2 as well. In this case, the formula applicable is
ln N/No = -kt
where N represents the masses before and after decay, t is the time elapsed and k is the decay rate constant.
Substituting,
ln 10/40 = -k*20
-k = <span>-0.0693
To find t1/2 or half life, then
ln 0.5 = -k*t1/2
t1/2 = ln 0.5 / 0.0693 = 0.1 minutes
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<span>Electronegative.
Electronegativity is the tendency for an atom to pull more electrons. Fluroine is the most electronegative element, and the trend is up and to the right of the periodic table, with the exception of the noble gases.</span>