Answer:
protons+neutrons = atomic mass
11+12 = 23
so the element which has an atomic mass of 23 is
<h2>Sodium (Na)</h2>
5.27 kJ of heat are required to heat 231 g of gold from 18 °C to 195 °C.
We have 231 g of gold at 18 °C and supply it with heat to increase its temperature to 195 °C. We can calculate the amount of heat required using the following expression.
where,
- <em>c: specific heat capacity of gold</em> (0.129 J/g.°C)
- ΔT: change in the temperature
5.27 kJ of heat are required to heat 231 g of gold from 18 °C to 195 °C.
You can learn more about heating here: brainly.com/question/1105305
Answer:
Ba(OH)2 + 2 HCl → BaCl2 + 2 H2O
The reactants are present in equimolar amounts, so there is no excess or limiting reactants.
(0.0500 L) x (0.600 mol/L HCl) x (2 mol H2O / 2 mol HCl) = 0.0300 mol H2O
(4.184 J/g·°C) x (50.0 g + 50.0 g) x (25.82 - 21.73)°C = 1711.256 J
(1711.256 J) / (0.0300 mol H2O) = 57042 J/mol = 57.0 kJ/mol H2O
Explanation:
You will need the Gas Law:
pV = nRT
Since T and p are constant, R is constant too, then moles increases->volume will increase with the same ratio too!
Balancing means there are equal amount of molecules on each side, both reactant and products. This is a method I like to do.
Under, I count how many molecules are in each side.
Cr2O3+Mg -->Cr + MgO
Cr: 2 1
O: 3 1
Mg: 1 1
Let's guess and make the number of oxygens equal on both sides.
Cr2O3+Mg -->Cr + 3MgO
Cr: 2 1
O: 3 3 EQUAL
Mg: 1 3
See what we did there? We multiplied the MgO on the products side by 3 so we can have 3 oxygens. Now let's multiply the Mg on the reactants by three so Mg AND O can be equal.
Cr2O3+3Mg -->Cr + 3 MgO
Cr: 2 1
O: 3 3 EQUAL
Mg: 3 3 EQUAL
Finally, we just need to multiply the loner Cr in the products side by two to make it equal for all elements.
Cr2O3+3Mg -->2Cr + 3 MgO
