A sour-tasting material (usually in a solution) that dissolves metals and other materials. Technically, a material that produces positive ions in solution. An acid<span> is the opposite of a base and has a pH of 0 to 7.</span>
Answer:
The two statements are all True for group 7 and 8 elements.
Explanation:
The Group 7 elements are known as the halogens. They are reactive non-metals and are always found in compounds with other elements. Chlorine, bromine and iodine are all halogens.
Chlorine, bromine and iodine are the three common Group 7 elements. Group 7 elements form salts when they react with metals. The term ‘halogen’ means 'salt former'.
In addition to the discription given to norble gases in the question which is true, norble gases;
- are inert gases located on the right of the periodic table.
- have a full-set of valence electrons, so they're stable, unreactive
- are colorless, odorless and tasteless.
- have low melting and low boiling points.
- can be found in small amounts in the Earth's crust and the Earth's atmosphere.
Answer:
The rocket is now too heavy to reach its destination.
Explanation:
In order to be able to calculate the volume of oxygen gas produced by this reaction, you need to know the conditions for pressure and temperature.
Since no mention of those conditions was made, I'll assume that the reaction takes place at STP, Standard Temperature and Pressure.
STP conditions are defined as a pressure of
100 kPa
and a temperature of
0
∘
C
. Under these conditions for pressure and temperature, one mole of any ideal gas occupies
22.7 L
- this is known as the molar volume of a gas at STP.
So, in order to find the volume of oxygen gas at STP, you need to know how many moles of oxygen are produced by this reaction.
The balanced chemical equation for this decomposition reaction looks like this
2
KClO
3(s]
heat
×
−−−→
2
KCl
(s]
+
3
O
2(g]
↑
⏐
⏐
Notice that you have a
2
:
3
mole ratio between potassium chlorate and oxygen gas.
This tells you that the reaction will always produce
3
2
times more moles of oxygen gas than the number of moles of potassium chlorate that underwent decomposition.
Use potassium chlorate's molar mass to determine how many moles you have in that
231-g
sample
231
g
⋅
1 mole KClO
3
122.55
g
=
1.885 moles KClO
3
Use the aforementioned mole ratio to determine how many moles of oxygen would be produced from this many moles of potassium chlorate
1.885
moles KClO
3
⋅
3
moles O
2
2
moles KClO
3
=
2.8275 moles O
2
So, what volume would this many moles occupy at STP?
2.8275
moles
⋅
22.7 L
1
mol
=
64.2 L
Answer:
A = 349 g.
Explanation:
Hello there!
In this case, since the radioactive decay kinetic model is based on the first-order kinetics whose integrated rate law is:
We can firstly calculate the rate constant given the half-life as shown below:
Therefore, we can next plug in the rate constant, elapsed time and initial mass of the radioactive to obtain:
Regards!
