The SI base unit for length is meter.
In order to make smaller measurements, you can use the centi-, milli-, micro-, etc. prefixes.
When you want to reference larger measurements, you can use the kilo-, mega-, giga- and prefixes such as those.
Answer:
C₃H₄O₄
Explanation:
In order to get the empirical formula of a compound, we have to follow a series of steps.
Step 1: Divide the percent by mass of each element by its atomic mass.
C: 34.6/12.01 = 2.88
H: 3.9/1.01 = 3.86
O: 61.5/16.00 = 3.84
Step 2: Divide all the numbers by the smallest one, i.e., 2.88
C: 2.88/2.88 = 1
H: 3.86/2.88 ≈ 1.34
O: 3.84/2.88 ≈ 1.33
Step 3: Multiply all the numbers by a number that makes all of them integer
C: 1 × 3 = 3
H: 1.34 × 3 = 4
O: 1.33 × 3 = 4
The empirical formula is C₃H₄O₄.
Answer:
47.36mL
Explanation:
Using Boyles law equation, which states that:
P1V1 = P2V2
Where;
V1 = initial volume (mL)
V2 = final volume (mL)
P1 = initial pressure (atm)
P2 = final pressure (atm)
Based on the provided information, V1 = 25.3mL, P1 = 152 kPa, V2 = ?, P2 = 0.804atm
First, we need to convert 152kPa to atm by dividing by 101
1kPa = 0.0099atm
152kPa = 1.505atm
P1V1 = P2V2
1.505 × 25.3 = 0.804 × V2
38.08 = 0.804V2
V2 = 38.08/0.804
V2 = 47.36mL
1. ₉¹⁹F
2. Mg(OH)₂
3. 2H₂ + O₂ ⇒ 2H₂O
<h3>Further explanation</h3>
1. Fluorine, atomic number : 9 , mass number = 19
Symbol : ₉¹⁹F
protons=electrons=atomic number = 9
neutrons = mass number - atomic mass

Configuration : [He] 2s² 2p⁵
2. Magnesium hydroxide is an ionic compound and is a strong base consisting of 2 ions:
Positive ion: Magnesium: Mg²⁺
negative ion: Hydroxide: OH⁻
The charges of the two are crossed, so that the compound becomes:
Mg(OH)₂
3. Reaction :
H₂ + O₂ --------> H₂O
give coefficient :
aH₂ + bO₂ --------> H₂O
H, left = 2a, right 2⇒2a=2⇒a=1
O, left = 2b, right 1⇒2b=1⇒b=0.5
Reaction becomes :
H₂ + 0.5O₂ --------> H₂O x 2
2H₂ + O₂ --------> 2H₂O
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