We know that the element Z = 119 would be placed right below the Fr, in the column of the alcaline metals.
We also know that the trend in the electronegativity is to decrease when you go up-down ia group.
The known electronegativities of the elements of this group are:
Li: 0.98
Na: 0.93
K: 0.82
Rb: 0.82
Cs: 0.79
Fr: 0.70
Then the hypotetical element Z = 119 would probably have an electronegativity slightly below 0.70, for sure in the range 0.60 - 0.70.
<span>Bases and Acids are chemically opposite from each other,and there are multiple ways to distinguish how they react when dissolved in water.
One accepted definition is that an acid is any chemical substance that, when it is dissolved in water, creates a solution with hydrogen ion activity greater than pure/neutral water. That is, it donates a proton to the solution. Any substance with a pH less than 7.0 is an acid, and includes substances such as vinegar and lemon juice.
By comparison, a base is any chemical substance that, when it is dissolved in water, creates a solution in which has hydrogen ion activity less than pure/neutral water. That is, it accepts protons. Any substance with a pH greater than 7.0 is a base, and includes substances such as ammonia and baking soda.</span>
Answer:
142.82 g
Explanation:
The following data were obtained from the question:
Volume of water = 12 mL
Volume of water + gold = 19.4 mL
Density of gol= 19.3 g/cm³
Mass of gold =.?
Next, we shall determine the volume of the gold. This can be obtained as follow:
Volume of water = 12 mL
Volume of water + gold = 19.4 mL
Volume of gold =.?
Volume of gold = (Volume of water + gold) – (Volume of water)
Volume of gold = 19.4 – 12
Volume of gold = 7.4 mL
Finally, we shall determine the mass of the gold as follow:
Note: 1 mL is equivalent to 1 cm³
Volume of gold = 7.4 mL
Density of gol= 19.3 g/cm³ = 19.3 g/mL
Mass of gold =?
Density = mass /volume
19.3 = mass of gold /7.4
Cross multiply
Mass of gold = 19.3 × 7.4
Mass of gold = 142.82 g
Therefore, the mass of the gold pebble is 142.82 g
Here is a universal law to balance chemical equations :
All chemical equations must be balanced
because of the law of conservation of mass.
It states that "matter
cannot be created or destroyed."
So, the number of atoms that you
start with at the beginning of the reaction must equal the number
of atoms that you end up with.
keeping this law in our mind,lets balance the<span> equation for the reaction of benzene and hydrogen to form cyclohexane.
</span><span>C 6 H 6 + H 2 → C 6 H 12.
Here is the balance chemical equation.
</span><span>2 C 6 H 6 + 6 H 2 → 2 C 6 H 12.</span>