Answer:
0.30 M
Explanation:
Using integrated rate law for first order kinetics as:
Where,
is the concentration at time t = ?
is the initial concentration = 1.36 M
k is the rate constant = 0.208 s⁻¹
t = 7.30 seconds
So,
a) When the reaction takes place a yellow precipitate will be formed.
b) The law of conservation of mass is true.
<u>Explanation:</u>
a) When a lead nitrate solution is mixed with a potassium chromate solution, a yellow precipitate containing lead forms according to the equation:
→ 
b) Law of conservation of mass for the given reaction is true.
From the given table we know the mass of reactants and its products.
Law of conservation of mass is a principle when a reaction takes place in a closed system, the mass of the products and reactants in the system doesn't change.
⇒The sum of the mass of the reactants = The sum of the mass of the products.
The sum of the reactants = 128.71+128.97.
= 257.68 g.
The sum of the products = 154.10+103.58.
= 257.68 g.
Thus law of conservation of mass is true for the above reaction.
Answer:
59.92 × 10²³ atoms are in 9.95 moles of iron
1.8 ×10²² molecules are in 0.03 moles of Carbon dioxide
1.19 moles are found in 7.20 x 10^23 atoms of platinum
Answer:
Metal
Element: Calcium
Valency: 2
Explanation:
To find the element, let's use the periodic table. (Look below)
We already went past 3 shells, just need the 2 electrons after it.
Just skip to the 4th row and count 2 to the right
We end up at Calcium.
Calcium is a metal and we're also on the alkaline earth metals column.
Calcium will need to lose 2 electrons to reach stability, so the valency is 2.