57 - True
58 - True
59 - True
60 - Fe and O
61 - Sr and F
62 - <span>both ionic and covalent bonds
Hope this helps!</span>
Answer:
19.3 g/mL
Explanation:
The following data were obtained from the question:
Mass (m) = 12.4 kg
Volume (V) = 642 mL.
Density (D) =.?
Next, we shall convert 12.4 kg to grams. This can be obtained as follow:
1 kg = 1000 g
Therefore,
12.4 kg = 12.4 × 1000
12.4 kg = 12400 g
Therefore, 12.4 kg is equivalent to 12400 g.
Finally, we shall determine the density of the gold as follow:
Density is simply defined as the mass of the substance per unit volume of the substance. It can be represented mathematically as:
Density (D) = mass (m) / volume (V)
D = m/V
With the above formula, the density of gold can easily be obtained as follow:
Mass (m) = 12400 g
Volume (V) = 642 mL.
Density (D) =.?
D = m/V
D = 12400/642
D = 19.3 g/mL
Therefore, the density of hold is 19.3 g/mL
House hold paint is a pure substance hope this helps :)
Answer:
Gold
Explanation:
Platinum has an atomic number of 78.
78 + 1 = 79
The element with atomic number 79 is Gold.
Hope this helps! Let me know if you have any questions :)
Answer:
E = 17 kJ
Explanation:
The enthalpy of the reaction is:
<u>Where</u>:
Ep: is the energy of the products
Er: is the energy of the reactants
Similarly, the enthalpy of the reaction is related to the activation energy forward (
) and to the activation energy reverse (
) as follows:
Having that ΔH = 44 kJ and
= 61 kJ, the activation energy of the reverse reaction is:
Therefore, the activation energy of the reverse reaction is 17 kJ.
I hope it helps you!