Answer:
<h2>0.02 moles </h2>
Explanation:
To find the number of moles in a substance given it's number of entities we use the formula
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
We have
We have the final answer as
<h3>0.02 moles</h3>
Hope this helps you
Answer:
The balanced chemical equation :
Explanation:
When calcium hydroxide reacts with hydrochloric acid it gives calcium chloride and water as a products. The chemical equation is given as:
According to question, solid calcium hydroxde is added to 38.0 mL of 0.410 M of HCl solution, so the chemical equation can be written as:
According to stoichiometry, when 1 mole of solid calcium hydroxide reacts with 1 mole of hydrochloric acid to gives 1 mole of aqueous calcium chloride and 1 mole of water.
<u>We are given:</u>
Initial Temperature = 90°c
Final Temperature = 120°c
Heat applied(ΔH) = 500 Joules
Specific heat(c) = 0.9 Joules / g°C
Mass of Aluminium(m) = ?
<u>Change in temperature:</u>
ΔT = Final temp. - Inital Temp.
ΔT = 120 - 90
ΔT = 30°c
<u>Calculating the mass:</u>
We know the formula:
ΔH = mcΔT
replacing the values:
500 = m(0.9)(30)
500 = m(27)
m = 500/27
m = 18.52 grams
The correct answer is the combination of a metal with another element.
An alloy is a combination of two or more metallic elements to make a stronger material. For instance, there are bronze alloys, brass alloys, and coin alloys.
We can confirm that an alloy is a combination of one metal with another metal because stainless steel is made of an iron and chromium alloy (iron is a metal; chromium is also a metal). Therefore, we can confirm that option C is the best choice.
