Make it stick
Subject decks with real saved review dates, difficulty ratings and a transparent spaced-repetition schedule.
Modified SM-2 schedule: Again → 10 minutes; Hard → at least 1 day; Good → 1 day, then 6 days, then interval × ease; Easy → 4 days or interval × ease × 1.3. History is saved on every rating. Review mode also works as a self-check quiz: reveal, compare, then rate honestly.
What makes active transport different from diffusion?
Reveal answer
Active transport moves substances against a concentration gradient using carrier proteins and energy from ATP. Diffusion is passive movement down a concentration gradient.
How are amount, mass and molar mass related?
Reveal answer
n = m / M. Use consistent mass units; n is in mol and M is commonly in g mol⁻¹.
Differentiate axⁿ with respect to x.
Reveal answer
d(axⁿ)/dx = anxⁿ⁻¹. Multiply by the power, then reduce the power by one.
How do reliability and validity differ?
Reveal answer
Reliability is consistency. Validity concerns whether a measure captures what it claims to measure. A measure can be reliable but invalid.