Answer:
Number of valence electrons stays the same
The specific heat capacity of copper metal : 0.390 J/g °C
<h3>Further explanation</h3>
Given
25 g metal
Δt metal = 18°C
15 g water
Δt water = 2.8 °C
Required
The specific heat capacity of copper metal
Solution
Q out = Q in
Q releases by metal = Q absorbed by water
m.c.Δt metal = m.c.Δt water(c water = 4.184 J/g °C)
25 x c x 18 = 15 x 4.18 x 2.8
c = 0.390 J/g °C
<u>Given:</u>
Enthalpy of decomposition of NO2 = 33.84 kJ/mol
<u>To determine:</u>
Enthalpy change when 2.5 moles of NO2 decomposes
<u>Explanation:</u>
The decomposition of NO2 is represented as:
2NO2(g) → N2(g) + 2O2(g)
Enthalpy change when 1 mole of NO2 decomposes is 33.84 kJ
therefore the enthalpy change corresponding to the decomposition of 2.50 moles of NO2 = 33.84 kJ * 2.40 moles/ 1 mole = 81.22 kJ
Ans: ΔH(decomposition) = 81.22 kJ
Ba stays as Ba+2 and Cl stays as Cl-
Rules that Casey breaks:
He didn't carefully examine the glassware before utilizing it.
Lab safety rules:
- Accidents do occur. Even a slight angle heating of the test tube can cause heating liquid to shoot out of the test tube. This is why the experimenter must always wear safety glasses and the test tube must be positioned away from any other individuals.
- Avoid smelling or tasting chemicals.
- Properly dispose of lab waste.
- Avoid self-experimenting.
- Avoid eating or drinking in the lab.
- Unless instructed otherwise by your teacher, never pour any chemicals down the sink.
- Always dispose of broken glass in the appropriate container. Never throw broken glass in the trash.
- Always be aware of where the safety equipment is and how to use it.
- Always leave your lab station completely clean. Always take your time and never leave any containers open.
Learn more about the lab safety rule here,
brainly.com/question/17221060
#SPJ4