Answer:
32.9%
Explanation:
<u>The mass of water </u>present in the original sample can be calculated by the substraction:
- m H₂O = sample mass before heating - sample mass after heating
- m H₂O = 8.24 g - 6.20 g = 2.04 g
The <u>percent by mass of water</u> can be calculated with the formula:
- Water Mass / Original Sample Mass * 100 %
* 100% = 32.9%
Answer:
<u>2</u>H₂S + <u>1</u>O₂ → <u>2</u>H₂O + <u>2</u>S
Explanation:
<u>SOLUTION :-</u>
Balance it by using 'hit & trial' method , and you'll get the answer :-
<u>2</u>H₂S + <u>1</u>O₂ → <u>2</u>H₂O + <u>2</u>S
<u></u>
<u>VERIFICATION :-</u>
<em>In reactant side of equation :-</em>
- Number of atoms in H = 2×2 = 4
- Number of atoms in S = 2×1 = 2
- Number of atoms in O = 1×2 = 2
<em>In product side of equation :-</em>
- Number of atoms in H = 2×2 = 4
- Number of atoms in O = 2×1 = 2
- Number of atoms in S = 2×1 = 2
Number of atoms of each element is equal in both reactant & product side of equation. Hence , the equation is balanced.
Answer:
See explanation below
Explanation:
To get this, we need to apply the general expression for half life decay:
N = N₀e(-λt) (1)
Where:
N and N₀ would be the final and innitial quantities, in this case, masses.
t: time required to decay
λ: factor related to half life
From the above expression we need λ and t. To get λ we use the following expression:
λ = t₁₂/ln2 (2)
And we have the value of half life, so, replacing we have:
λ = 8.04 / ln2 = 11.6
Now, we can replace in (1) and then, solve for t:
0.75 = 40 exp(-11.6t)
0.75 / 40 = exp(-11.6t)
ln(0.01875) = -11.6t
-3.9766 = -11.6t
t = -3.9766 / -11.6
<h2>
t = 0.34 days</h2><h2>
</h2>
Physical changes happen when you do/mix something that can be reversed. Best example is ripping a paper, you can just tape it back together so it is just an observable thing that changes, which is a physical change. Chemical changes happen when you mix things and they make a new substance and can’t be reversed. The best example of this is the Statue of Liberty, which changed in color due to the chemical change between the oxygen and copper, which created a new substance (rust) which made it green instead of copper.
Sorry for the long answer but hope this helps!
Answer:
Answer
Explanation:
The second one is three, the last one is four, six is nine, fouris ten, eight is one, three is eight, seven is seven, five is five, three is six, one is two.
PLS Im only partly sure about a few but this is my answer.
