Answer:
C
cell wall only in plants
chloroplast only in plants
enlarged vacuoles only in plants
cell membrane in both
hope this helps :)
Explanation:
Will be destroyed unless helped.
The answer is 1/16.
Half-life is the time required for the amount of a sample to half its value.
To calculate this, we will use the following formulas:
1.

,
where:
<span>n - a number of half-lives
</span>x - a remained fraction of a sample
2.

where:
<span>

- half-life
</span>t - <span>total time elapsed
</span><span>n - a number of half-lives
</span>
So, we know:
t = 10 min
<span>

= 2.5 min
We need:
n = ?
x = ?
</span>
We could first use the second equation to calculate n:
<span>If:

,
</span>Then:

⇒

⇒

<span>
</span>
Now we can use the first equation to calculate the remained fraction of the sample.
<span>

</span>⇒

<span>⇒

</span>
Answer:
Mass = 2.8 g
Explanation:
Given data:
Mass of HCl = 102 g
Mass of Zn = 128 g
Mass of H₂ = ?
Solution:
Chemical equation:
2HCl + Zn → H₂ + ZnCl₂
Number of moles of Zn:
Number of moles = mass/molar mass
Number of moles = 128 g/ 65.38 g/mol
Number of moles = 2 mol
Number of moles of HCl:
Number of moles = mass/molar mass
Number of moles = 102 g/ 36.5 g/mol
Number of moles = 2.8 mol
Now we will compare the moles of hydrogen gas with HCl and Zn.
HCl : H₂
2 : 1
2.8 : 1/2×2.8 = 1.4 mol
Zn : H₂
1 : 1
2 : 2
Number of moles of hydrogen formed by HCl are less thus it will limiting reactant.
Mass of Hydrogen:
Mass = number of moles × molar mass
Mass = 1.4 mol × 2 g/mol
Mass = 2.8 g