Answer:
Answer is explained below:
Explanation:
Your feet rub electrons off the carpet so, when we walk on carpeted floor more electrons move into our body and this is because of static electricity. Static electricity is stationary electric charge, generally produced by friction.
Answer:
D - chemical and physical
Explanation:
Only chemical and physical changes can reach the level of dynamic equilibrium. Nuclear reactions cannot reach dynamic equilibrium.
- A system is in dynamic equilibrium when the rate of forward reaction is the same as that of backward reaction in a reversible reaction.
- Nuclear reactions cannot be reversed.
- Dynamic equilibrium is prominent in chemical reactions. It is commonly found that as a reaction occurs, the backward and forward reactions can reach equilibrium levels.
- In physical changes, this can also occur when certain conditions of pressure and temperatures are satisfied.
A(n) Acute exposure is a short term or brief exposure that may create an immediate health hazard. Answer: A)
Answer:
Ba^2+(aq) + 2OH-(aq) + 2H+(aq) + SO4^2-(aq) → BaSO4(s) + 2H2O(l)
Explanation:
Step 1: Data given
the contribution of protons from H2SO4 is near 100 %.
Step 2: The unbalanced equation
.Ba(OH)2(aq) + H2SO4(aq) → BaSO4(s) + H2O(l)
Step 3: Balancing the equation
On the left side we have 4x H (2x in Ba(OH)2 and 2x in H2SO4). On the right side, we have 2x H (in H2O).
To balance the amount of H on both sides, we have to muliply H2O (on the right side) by 2.
Ba(OH)2(aq) + H2SO4(aq) → BaSO4(s) + 2H2O(l)
Step 4: The net ionic equation
The net ionic equation, for which spectator ions are omitted - remember that spectator ions are those ions located on both sides of the equation - will.
Ba^2+(aq) + 2OH-(aq) + 2H+(aq) + SO4^2-(aq) → BaSO4(s) + 2H2O(l)
After canceling those spectator ions in both side, look like this:
Ba^2+(aq) + 2OH-(aq) + 2H+(aq) + SO4^2-(aq) → BaSO4(s) + 2H2O(l)
Answer:
Jeweler B = more accurate
Jeweler A = more precise
Error:
0.008, 0
% error :
0.934% ; 0
Explanation:
Given that:
True mass of nugget = 0.856
Jeweler A: 0.863 g, 0.869 g, 0.859 g
Jeweler B: 0.875 g, 0.834 g, 0.858 g
Official measurement (A) = 0.863 + 0.869 + 0.859 = 2.591 / 3 = 0.864
Official measurement (B) = 0.875 + 0.834 + 0.858 = 2.567 / 3 = 0.8556
Accuracy = closeness of a measurement to the true value
Accuracy = true value - official measurement
Jeweler A's accuracy :
0.856 - 0.864 = - 0.008
Jeweler B's accuracy :
0.856 - 0.856 = 0.00
Therefore, Jeweler B's official measurement is more accurate as it is more close to the true value of the gold nugget.
However, Jeweler A's official measurement is more precise as each Jeweler A's measurement are closer to one another than Jeweler B's measurement which are more spread out.
Error:
Jeweler A's error :
0.864 - 0.856 = 0.008
% error =( error / true value) × 100
% error = (0.008/0.856) × 100% = 0.934%
Jeweler B's error :
0.856 - 0.856 = 0 ( since the official measurement as been rounded to match the decimal representation of the true value)
% error = 0%
