Answer: The final temperature of nickel and water is
.
Explanation:
The given data is as follows.
Mass of water, m = 55.0 g,
Initial temp,
,
Final temp,
= ?,
Specific heat of water = 4.184
,
Now, we will calculate the heat energy as follows.
q = 
= 
Also,
mass of Ni, m = 15.0 g,
Initial temperature,
,
Final temperature,
= ?
Specific heat of nickel = 0.444 
Hence, we will calculate the heat energy as follows.
q = 
=
Therefore, heat energy lost by the alloy is equal to the heat energy gained by the water.

= -(
)
= 
Thus, we can conclude that the final temperature of nickel and water is
.
One of the greatest examples of entropy working in everyday life is the fact that a messy room is the norm. So if you clean your room it will likely become messy over a period of time, and work will have to be put in to make it orderly again.
BaSO₄ is relatively harmless, but BaS is highly toxic.
BaSO₄ is quite insoluble (240 µg/100 mL). It is a <em>mild irritant</em> in cases of skin contact and inhalation. However, it is <em>safe enough</em> that health professionals ask patients to drink a suspension of BaSO₄. The Ba is opaque to X-rays, so it makes the stomach and intestines more visible to radiographers.
BaS is soluble (7.7 g/100 mL). It reacts slowly with water and more rapidly in the acid conditions of the stomach to <em>release H₂S</em>.
BaS + 2HCl ⟶ BaCl₂ + H₂S
An H₂S concentration of 60 mg/100 mL can be <em>fatal within 30 min</em>.
<em>Don’t eat barium sulfide!</em>
The false positive from the response of hydrogen peroxide and the immunizing circle would be created by poor specificity. The recipe for specificity is TN/TN+FP. False-positive outcomes can be ascribed to meddling substances in nature where the strips are put away or utilized, for example, hydrogen peroxide (H2O2) or fade (hypochlorite).
2K + Br₂ = 2KBr
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