Answer: 0.0043mole
Explanation:Please see attachment for explanation
Answer:
The element is Na
Explanation:
Ionization energy is the energy needed to release the last electron from an atom in its ground state to the gaseous state. It is a periodic property that increases as we go through the periods of the periodic table, but decreases if we move in groups. Sodium has thr ionic radius (another periodic property) that is too large, making it easier to release the electron away, since it is too far from the nucleus.
Empirical formula of a compound gives the proportions of the elements in that compound but it does not define the actual arrangement and number of atoms.
Let the empirical formula of compound be 
.
The ratio of number of moles of C, H and O can be calculated as follows:
Simplifying the ratio,
Thus, the value of x, y and z will be 1, 2 and 1 respectively.
Therefore, the empirical formula will be 
.
<span>If the aqueous solution is 34% Licl then it is 100 - 34% water = 66%
From the calculation we've found out that it is 66% water. Then we need to find the weight from a 250 g solution.
66/100 * 250 = 165g
Hence it is 165g</span>
Answer:
The correct option is D.
Explanation:
Radioactive substances usually emit different types of particles when they are decaying. Such particles include alpha particles, beta particles and gamma ray. When an alpha particle is emitted from an unstable radioactive nucleus such nucleus usually lost an atomic mass that correspond to that of helium atom. Note that an alpha particle is made up of two protons and two neutrons, which result in mass number of 4. Thus, a nucleus that emit an alpha particle will have its mass number (atomic mass) reduce by 4 and atomic number that is reduced by 2.
