Answer: The last one
Explanation: because Im in the 8th grade and I did this in the 6th
GIVE BRAINLEIST LIKE U PROMISED
Dull (not shiny)
poor conductors of heat and electricity (they are insulators)
weak and brittle (they easily break or shatter when solid)
Answer:
18.94%.
Explanation:
- The decay of carbon-14 is a first order reaction.
- The rate constant of the reaction (k) in a first order reaction = ln (2)/half-life = 0.693/(5730 year) = 1.21 x 10⁻⁴ year⁻¹.
- The integration law of a first order reaction is:
<em>kt = ln [A₀]/[A]</em>
k is the rate constant = 1.21 x 10⁻⁴ year⁻¹.
t is the time = 13,750 years.
[A₀] is the initial percentage of carbon-14 = 100.0 %.
[A] is the remaining percentage of carbon-14 = ??? %.
∵ kt = ln [Ao]/[A]
∴ (1.21 x 10⁻⁴ year⁻¹)(13,750 years) = ln (100.0%)/[A]
1.664 = ln (100.0%)/[A]
Taking exponential for both sides:
5.279 = (100.0%)/[A]
<em>∴ [A]</em> = (100.0%)/5.279 = <em>18.94%.</em>
Answer: The new volume is 53.3 ml
Explanation:
The combined gas equation is,
where,
= initial pressure of gas = 50.0 kPa
= final pressure of gas = 80.0 kPa
= initial volume of gas = 80.0 ml
= final volume of gas = ?
= initial temperature of gas = 
= final temperature of gas = 
Now put all the given values in the above equation, we get:
The new volume is 53.3 ml
Physical change can change a substance by affecting the form of a chemical change.
Examples of physical changes:
Something cut (Paper)
Molded (Bread)
Boiled (Water)
Mixed (Berries and strawberries)
HOPE THIS HELPS YOU! ^_^
