Answer:
2 atm
Explanation:
Chemical reactions are carried out at a certain rate. Sometimes that rate is quite slow, so we want to speed things up, which is usually used by increasing temperature, increasing pressure or adding a catalyst (a substance that increases the rate without changing itself).
If this is the case, then, when writing a chemical equation, we state these special conditions over a right arrow.
Now let's look at the answers:
- 25°C is a value and unit of temperature
- ∆ is a symbol that denotes change
- 2 atm is a value and unit of pressure (atmosphere is old unit for pressure)
- Pt is a chemical symbol for platinum, an element often used as a catalyst.
So, the correct answer is C) 2 atm
Answer:
The ground state configuration is the lowest energy, most stable arrangement. An excited state configuration is a higher energy arrangement (it requires energy input to create an excited state). Valence electrons are the electrons utilised for bonding.
or the
FIGURE 5.9 The arrow shows a second way of remembering the order in which sublevels fill. Table 5.2 shows the electron configurations of the elements with atomic numbers 1 through 18.
Element Atomic number Electron configuration
sulfur 16 1s22s22p63s23p4
chlorine 17 1s22s22p63s23p5
argon 18 1s22s22p63s23p6
or the
Two electrons
Two electrons fill the 1s orbital, and the third electron then fills the 2s orbital. Its electron configuration is 1s22s1.
Explanation:
<em>Choose </em><em>your </em><em>answer </em>
<em>brainlilest </em><em>me</em>
<em><u>CARRY </u></em><em><u>ON </u></em><em><u>LEARNING</u></em>
Answer:
[OH⁻] = 4.3 x 10⁻¹¹M in OH⁻ ions.
Explanation:
Assuming the source of the carbonate ion is from a Group IA carbonate salt (e.g.; Na₂CO₃), then 0.115M Na₂CO₃(aq) => 2(0.115)M Na⁺(aq) + 0.115M CO₃²⁻(aq). The 0.115M CO₃²⁻ then reacts with water to give 0.115M carbonic acid; H₂CO₃(aq) in equilibrium with H⁺(aq) and HCO₃⁻(aq) as the 1st ionization step.
Analysis:
H₂CO₃(aq) ⇄ H⁺(aq) + HCO₃⁻(aq); Ka(1) = 4.3 x 10⁻⁷
C(i) 0.115M 0 0
ΔC -x +x +x
C(eq) 0.115M - x x x
≅ 0.115M
Ka(1) = [H⁺(aq)][HCO₃⁻(aq)]/[H₂CO₃(aq)] = [(x)(x)/(0.115)]M = [x²/0.115]M
= 4.3 x 10⁻⁷ => x = [H⁺(aq)]₁ = SqrRt(4.3 x 10⁻⁷ · 0.115)M = 2.32 x 10⁻⁴M in H⁺ ions.
In general, it is assumed that all of the hydronium ion comes from the 1st ionization step as adding 10⁻¹¹ to 10⁻⁷ would be an insignificant change in H⁺ ion concentration. Therefore, using 2.32 x 10⁻⁴M in H⁺ ion concentration, the hydroxide ion concentration is then calculated from
[H⁺][OH⁻] = Kw => [OH⁻] = (1 x 10⁻¹⁴/2.32 x 10⁻⁴)M = 4.3 x 10⁻¹¹M in OH⁻ ions.
________________________________________________________
NOTE: The 2.32 x 10⁻⁴M value for [H⁺] is reasonable for carbonic acid solution with pH ≅ 3.5 - 4.0.
Equation: MgOH2 (s) --> MgO (s) + H2O (g)
And it's already balanced.
I had chemistry this semester too.
Which of the protist is the most complex organism ?
A) paramecium
<u>B) amoeba
</u>
C) Euglena
D) Volvox
