Chemistry and Materials Science Flashcards
6 cards from real EIT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Chemistry and Materials Science flashcards as text
Which type of bond results from the sharing of electrons between two atoms?
Answer: Covalent bond
Covalent bonds form when atoms share electron pairs, as in H₂, H₂O, and organic molecules.
The yield strength of a material is defined as the stress at which:
Answer: Significant permanent (plastic) deformation begins
Yield strength marks the onset of plastic deformation — below this stress, deformation is elastic and recoverable.
In an iron-carbon phase diagram, the eutectoid composition occurs at approximately:
Answer: 0.76 wt% C at 727°C
The eutectoid point in the Fe-C system is 0.76 wt% C at 727°C, where austenite transforms to pearlite (ferrite + cementite).
The rate of a chemical reaction generally __________ with increasing temperature.
Answer: Increases exponentially (Arrhenius)
Arrhenius equation k = Ae^(−Ea/RT) shows exponential increase in rate constant k with temperature T.
Polymer glass transition temperature (Tg) is the temperature below which the polymer becomes:
Answer: Rigid and glassy (brittle)
Below Tg, chain mobility freezes and the polymer becomes stiff and brittle like glass; above Tg it is rubbery.
Le Chatelier's principle states that if a stress is applied to a system at equilibrium, the system will:
Answer: Shift to partially counteract the applied stress
Le Chatelier's principle predicts that equilibrium shifts in the direction that opposes the imposed change (stress).