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
The <span>12C</span><span> isotope. Hope this helps.</span>
Answer:
2Al + 3H2SO4 → Al2(SO4)3 + 3H2
2Fe + 3Cl2 → 2FeCl3
Explanation:
1. (SO4) 3 you see this 3 it means that 3 must be behind H2SO4. So now it's 3H2SO4.
2. If 3 is now behind one H2, it must be behind the other.
So now it's 3H2.
3. Al2 (SO4) 3 has 2 ahead of Al which means there will be 2Al in the reactants.
1. FeCl3 has 3 ahead of Cl, and Cl2 has 2. Which means that behind FeCl3 goes 2, and behind Cl2 goes 3 so now we have equated all Cl.
2. Since it is now 2FeCl3, we know that there must be 2 in the second Fe. It's 2Fe now.
Answer:- Frequency is
.
Solution:- frequency and wavelength are inversely proportional to each other and the equation used is:

where,
is frequency, c is speed of light and
is the wavelength.
Speed of light is
.
We need to convert the wavelength from nm to m.
(
)

= 
Now, let's plug in the values in the equation to calculate the frequency:

=
or 
since, 
So, the frequency of the green light photon is
.
Answer:
(1) I shifts toward product and II shifts toward reactant.
Explanation:
Increasing the temperature of an endothermic reaction (∆H is positive) shifts the equilibrium position to the right thus favoring product formation.
Increasing the temperature of an exothermic reaction (∆H is negative) shifts the equilibrium position to the left thus favoring the backward reaction.