Answer:
410.196 J/[kg*°C].
Explanation:
1) the equation of the energy is: E=c*m*(t₂-t₁), where E - energy (523 J), c - unknown specific heat of copper, m - mass of this copper [kg], t₂ - the final temperature, t₁ - initial temerature;
2) the specific heat of copper is:
![c=\frac{E}{m*(t_2-t_1)}; \ => \ c=\frac{523}{0.085*(45-30)}=\frac{523}{1.275}=410.196[\frac{J}{kg*C}].](https://tex.z-dn.net/?f=c%3D%5Cfrac%7BE%7D%7Bm%2A%28t_2-t_1%29%7D%3B%20%5C%20%3D%3E%20%5C%20c%3D%5Cfrac%7B523%7D%7B0.085%2A%2845-30%29%7D%3D%5Cfrac%7B523%7D%7B1.275%7D%3D410.196%5B%5Cfrac%7BJ%7D%7Bkg%2AC%7D%5D.)
Explanation:
here's the answer to your question about
Answer:
By repelling water, the tiny water striders stand on the water's surface and the captured airs allows them to float and move easily. so number 2. Surface Tension.
Explanation:
The attraction between water molecules creates tension and a very delicate membrane. Water striders walk on this membrane. ... The legs have tiny hairs that repel water and capture air.
Se2- has 34 protons and 36 electrons so it gets a 2- charge.
Answer:
5.25 moles.
Explanation:
The decomposition reaction of NaN₃ is as follows :

We need to find how many grams of N₂ produced in the process.
From the above balanced chemical reaction, we conclude that the ratio of moles of sodium azide and nitrogen gas are 2 : 3.
2 moles of sodium azide decomposes to give 3 moles of nitrogen gas. So,
3.5 moles of sodium azide decomposes to give
moles of nitrogen gas.
Hence, the number of moles produced is 5.25 moles.