Since obliquity is the angle between the axis of rotation and the direction perpendicular to the orbital plane, it changes as the orbital plane changes due to the influence of other planets. But the axis of rotation can also move (axial precession), due to torque exerted by the sun on a planet's equatorial bulge.
(Got it from google )
Answer:
7,94 minutes
Explanation:
If the descomposition of HBr(gr) into elemental species have a rate constant, then this reaction belongs to a zero-order reaction kinetics, where the r<em>eaction rate does not depend on the concentration of the reactants. </em>
For the zero-order reactions, concentration-time equation can be written as follows:
[A] = - Kt + [Ao]
where:
- [A]: concentration of the reactant A at the <em>t </em>time,
- [A]o: initial concentration of the reactant A,
- K: rate constant,
- t: elapsed time of the reaction
<u>To solve the problem, we just replace our data in the concentration-time equation, and we clear the value of t.</u>
Data:
K = 4.2 ×10−3atm/s,
[A]o=[HBr]o= 2 atm,
[A]=[HBr]=0 atm (all HBr(g) is gone)
<em>We clear the incognita :</em>
[A] = - Kt + [Ao]............. Kt = [Ao] - [A]
t = ([Ao] - [A])/K
<em>We replace the numerical values:</em>
t = (2 atm - 0 atm)/4.2 ×10−3atm/s = 476,19 s = 7,94 minutes
So, we need 7,94 minutes to achieve complete conversion into elements ([HBr]=0).
Answer:
5230J
Explanation:
Mass (m) = 250g
Initial temperature (T1) = 25°C
Final temperature (T2) = 30°C
Specific heat capacity (c) = 4.184J/g°C
Heat energy (Q) = ?
Heat energy (Q) = Mc∇T
Q = heat energy
M = mass of the substance
C = specific heat capacity
∇T = change in temperature = T2 - T1
Q = 250 × 4.184 × (30 - 25)
Q = 1046 ×5
Q = 5230J
The heat energy required to raise the temperature of 250g of water from 25°C to 30°C is 5230J
