Answer:
19
Explanation:
Once you add all the weights together, you end up with 114 then you divide it by how many dogs there are, 6. 114/6 = 19. The average is 19 lbs.
Answer: 1. AgF + CaCl2 = AgCl + CaF2
2. C2H4 +O2 = CO2 +H2O
3. K2S = K+S
4. O2 + Mg = MgO
5. Mg + AlBr3 = MgBr2 + Al
6.C2H6O + O2= CO2 + H2O
7.Li2SO4 + MgCl2= Li2SO4 + MgCl2
8.HCl + Zn= H2 + ZnCl2
Explanation:
Balance the equation
Write down your given equation.
Write down the number of atoms per each element that you have on each side of the equation.
Always leave hydrogen and oxygen for last.
If you have more than one element left to balance:
Add a coefficient to the single carbon atom on the right of the equation to balance it with the 3 carbon atoms on the left of the equation.
Balance the hydrogen atoms next.
Balance the oxygen atoms.
<span>
Correct Answer:
Option 3 i.e. 30 g of KI dissolved in 100 g of water.
Reason:
Depression in freezing point is a
colligative property and it is directly proportional to molality of solution.
Molality of solution is mathematically expressed as,
Molality = </span>
<span>
In case of
option 1 and 2, molality of solution is
0.602 m. For
option 3, molality of solution is
1.807 m, while in case of
option 4, molality of solution is
1.205 m.
<u><em>Thus, second solution (option 2) has highest concentration (in terms of molality). Hence, it will have lowest freezing point</em></u></span>
<h3>
Answer:</h3>
Lead-205 (Pb-205)
<h3>
Explanation:</h3>
<u>We are given;</u>
We are supposed to identify its product after an alpha decay;
- Polonium-209 has a mass number of 209 and an atomic number of 84.
- When an element undergoes an alpha decay, the mass number decreases by 4 while the atomic number decreases by 2.
- Therefore, when Po-209 undergoes alpha decay it results to the formation of a product with a mass number of 205 and atomic number of 82.
- The product from this decay is Pb-205, because Pb-205 has a mass number of 205 and atomic number 82.
- The equation for the decay is;
²⁰⁹₈₄Po → ²⁰⁵₈₂Pb + ⁴₂He
- Note; An alpha particle is represented by a helium nucleus, ⁴₂He.
Answer:
No, in science their meanings are not the same as their everyday meanings.
Explanation:
In Science, Precision and Accuracy are defined as,
Accuracy:
Accuracy is the value which is closest to the known or standard value.
Precision:
While, Precision is the value of closeness of two measured values to each other.
Example:
Let suppose in Chemistry Lab you weight an object as 50 g. While the actual weight of that object is 30 g. It means your reading is not accurate.
On second measurement you find that the object weight is 31 g. This time your reading is not precise.
