When we increase the surface area of an object, more atoms are exposed. Since more atoms are exposed, the atoms can react faster, and this is why the rate of a reaction increases when the surface area increases.
For example, lets say we want to heat a potato. If we just put the whole potato in the microwave, it will take a long time for the potato to get thoroughly heated. However, if we chop the potato into smaller pieces, we will observe that it gets heated much faster. This is because we increased the surface area of the potato, which resulted in more potato atoms to be exposed to the heat, and caused the reaction to be faster.
Answer:
The correct answer is - 2Cu + 4HBr → 2H[CuBr2] + H2
Explanation:
Copper (Cu) and hydrobromic acid (HBr), which is a dissolved form of hydrogen bromide in the water, react and produce hydrogen dibromidocuprate (I) and hydrogen molecules.
The complete and balanced equation is -
2Cu + 4HBr → 2H[CuBr2] + H2
This reaction takes place in the medium of ester. Copper is in the suspension form in this reaction.
Thus, the correct answer is - 2Cu + 4HBr → 2H[CuBr2] + H2
Answer:
You cannot make observations if you are 57 seconds late into the lab.
Explanation:
The atomic nucleus can split by decay into 2 or more particles as a result of the instability of its atomic nucleus due to the fact that radioactive elements possess an unstable atomic nucleus.
Now, the primary particles which are emitted by radioactive elements in order to make them decay are alpha, beta & gamma particles.
The half life equation is;
N_t = N₀(½)^(t/t_½)
Where:
t = duration of decay
t_½ = half-life
N₀ = number of radioactive atoms initially
N_t = number of radioactive atoms remaining after decay over time t
We are given;
t = 57 secs
N₀ = 100 g
Now, half life of Nitrogen-16 from online sources is 7.2 seconds. t_½ = 7.2
Thus;
N_t = 100(1/2)^(57/7.2)
N_t = 0.4139g
We are told that In order to make observations, you require at least .5g of material.
The value of N_t you got is less than 0.5g, therefore you cannot make observations if you are 57 seconds late.
Answer:
40.02 calories
Explanation:
V = 10 mL = 10g
we know t went <em>up</em> by 4°C, this is our ∆t as it is a change.
Formula that ties it together: Q = mc∆t
where,
Q = energy absorbed by water
m = mass of water
c = specific heat of water (constant)
∆t = temperature change
Q = (10 g) x (4.186 J/g•°C) x (4°C)
Q = 167.44 J
Joules to Calories:
167.44 J x 1 cal/4.184 J = 40.02 calories
(makes sense as in image it is close to the value).
Answer:
Interacting with animals has been shown to decrease levels of cortisol (a stress-related hormone) and lower blood pressure. Other studies have found that animals can reduce loneliness, increase feelings of social support, and boost your mood.
Explanation:
