Seniorhighub

What name is given to an action such as the generation of action potential by a neuron which occurs either completely or not at all.

In a particular type of organism eggs ends sperms have 5 chromosomes but other cells have 10 chromosomes. Observations like this inspired a particular type of hypothesis. What is that type of hypothesis?

A buffer is prepared by adding 50.0cm² of 0.100mol/dm³ KOH solution to 150cm² of 0.100mol/dm³ ethanoic acid. Calculate the pH of the resulting buffer. Pka of ethanoic acid is 4.76. You may give your answer as a logarithm expression.

The buffer prepared by adding 150cm³ of 0.100mol/dm³ ethanoic acid solution to 50.0 cm³ of 0.100 mol/dm³ KOH solution is not the best buffer that can be prepared with those two reagent. What can be done to obtain a better buffer?

Explain why phenolthaline is a suitable indicator for the titration of solution of ethanoic acid and NaOH.

Solve for x given 125^x+1 = 1/25

Find the solution set for the quadratic inequality x² – 3x -4 < 0.

If the vectors a = 2i +3j and b = 3xi + 10j are perpendicular. Find the value of x.

What is the work done by 3 mole of an ideal gas when it expands from 20m3 to 25m³ at a constant pressure of 200.

A 50 g pellet is launch at 80 m/s vertically upward from the ground. How long does the pellet remain air bound?

Express 500 e.V in S. I. base unit.

Give one property shared by chloroplasts and mitochondria.

In genetics, a genotypic ratio of 1: 2: 1 in the offspring of a hybrid cross illustrates which law?

Name the organelle that is always found in pairs.

Find the number of significant figures in the number 0.0150.

The ratio of the areas of two circles is 49 ∶ 25.

Find the next term in the sequence 5, 7, 12, 19, 31, . . .

Which of these two acids will be stronger, 2-chlorobutanoic acid and 3-chlorobutanoic.

Which element will be discharged in greater mass by one Faraday of charge in an electrolysis? Sodium salt or aluminium salt.

Which polymer is most likely to be used for plastic chairs?

From what height must an object be dropped to strike the ground with a speed of 20 m s^-1?

The work function of a photocathode is 2.5 eV. What is the kinetic energy of the most energetic electrons emitted from the photocathode when 2.4 eV photons fall on it?

The moment of inertia of an object about a certain axis is 50 kg m². What torque is required to spin the object about that axis at an angular acceleration of 4 rad s^-2?

A meter bridge connected as potentiometer is calibrated with a 1.20V cell with gives null deflection when one of it terminals is connected to the 0 cm mark and the jockey is on the 45.0 cm mark. Find the emf of a similarly connected cell which gives null deflection when the jockey is on the 54.0cm mark.

The terminal efficiency of an internal combustion energy is 25%. Find the mechanical power developed by the engine when it consume fuel whose heat of combustion is 35MJ/dm3 at the rate of 4.0 * 10-4dm3/s.

A high frequency transformer has 20 primary chains and 5 secondary chains wound on a ferrite core. Find the secondary rms voltage when the primary is excited by a signed wave whose rms voltage is 8 volts

When scandium -45 , atomic number 21 is bombarded with neutrons it captures 1 and disintegrate to give a new nuclide of mass number 42 and an alpha particle. Give the atomic number of the new nuclide and identify the element.

When sulphur- 33 , atomic number 16 is bombarded with neutrons it captures 1 to form phosphorus- 33, atomic number 15 and emit a nuclei particle. Give a balanced equation and the identity of the nuclei particle.

What is the most likely reason for the development of resistance against pesticide in insect damaging a crop.

Name the process through which the diploid number of chromosomes of organisms is re-established

state the principle by which a photometer works

Evaluate log164(log416)

Find the value(s) of x given that the vector a = xi + 7j has magnitude 25

Identify the polygon, the sum of whose interior angles is 5∏ radians

In the electrolysis of copper (II) tetraoxosulphate (VI) solution using platinum electrodes, which substance is formed at the anode?

In the electrolysis of concentrated NaCl solution using graphite electrodes, which substance is formed at the cathode?

In electrolysis what type of current is used?

What is the acceleration of a vehicle moving at 5 m/s that rounds without skidding, a curve of radius 50 m in a flat road?

The energy of a blue-green photon is 2.5 eV. What is the energy , in eV, of a photon whose wavelength is five times the wavelength of the blue-green photon?

Solar energy is converted into electrical energy which is then converted into mechanical energy. Give the appropriate devices that link the stages in this energy transformation chain.

Which organelle in eukaryotic cells shows striking similarities to bacteria?

What name is given to the region enclosed by the inner membrane of the mitochondria?

Name the class of organelles to which chloroplasts belong.

A bank charges interest at GH¢ 2,000.00 monthly on a loan of GH¢ 100,000.00. Find the annual rate of interest.

If sinϰ = ½ and ϰ is acute, find ϰ in radians.

P and Q are statements such that P is true and Q false. Find the truth value of the compound statement 'P and not Q'.

What is the most common form of carbohydrate?

What does the velocity ratio of a simple machine signify?

Find the focal length of a spherical mirror whose radius of curvature is 80 cm.

A body moves from a point 5 m due east to a point 3 m due west in 40 s. Find the average velocity.

A translation maps (2, 4) into (4, 2). Find the image of the point A(3, 1).

Find the number of axes of symmetry of a regular pentagon.

Find the number of significant figures of the number 350.

Name the product that will be formed when butanoic acid is heated with PCI₅

Find the length of a simple pendulum whose angular frequency is 1 rad / s.

State the conditions under which Newton's Third Law applies to the collision between two bodies.

At what point in the path of a particle executing simple harmonic motion is the acceleration of the particle zero.

How many edges has a tetrahedron?

Evaluate Tan 240°

Find the next prime after 163.

Name the tissue in plants where the root hairs originate.

What is the basic difference between white blood cells and red blood cells in terms of their function?

What is the function of lymph nodes?

What colour is produced on adding Potassium thiocyanate (KSCN) solution to iron (II) solution.

Give the oxidation state of chlorine in the molecule HCIO₄.

What is the colour of the precipitate produced when potassium hexacyanoferrate (III) is added to iron (II)

Find the measure of two supplementary angles if one measure is thrice the other.

Determine whether the lines with equations y = 2ϰ + 3, and y = -2x + 3 are parallel, perpendicular or neither.

What name is given to the rapid growth of populations of algae in either freshwater or saltwater environments?

What name is given to the increase in the growth of algae due to the build-up of nutrients in a lake.

What is the important function of the operculum in mosses?

State fully the acid functional group of phenol.

How many carbons are present in a molecule of 2-methyleicosane

What is the name of a long chain saturated hydrocarbon with 11 carbons in a chain?

What is the atomic number of tritium?

What is the weight of a floating object which displaces 0.5 m³ of water?

The working substance of a heat engine absorbs 10 kJ of thermal energy from a hot reservoir and rejects 8kJ to a cold reservoir in one cycle. What is the work done by the engine?

The reactance of an inductor is 20Ω at an angular frequency of 50 rads s^-1. Find the inductance of the inductor.

A 5 kg object moving at 20 m s^-1 slows to 18 m s^-1 in 0.5 s. Find the magnitude of the average force on the object.

The half-life of a radionuclide is 2 m s. What fraction of active nuclei remains in a sample of the radionuclide after 4 m s?

What name is given to animal-like protists?

What structure collects extra water and expels it from the cell.

What name is given to the active growing stage of a protozoan parasite?

Solve the linear equation 3(ϰ - 2) - 5(1 – 2ϰ) = 15.

Find the general term of the given sequence 3, -6, 12, -24, . . .

Given the functions f(ϰ) = 3ϰ + 2 and g(ϰ) = ϰ² – 2, find the composite function f(g(ϰ)).

State the colour of chlorine gas.

State the colour of copper (I) oxide.

Give the colour that a copper compound imparts to a colourless flame.

What is the mechanical advantage of a frictionless inclined plane which is inclined at 30° to the horizontal?

What is the ground state energy, in electron volts, of the electron in a hydrogen atom and what is the physical significance of its sign?

How does the rms speed of ideal gas molecules vary with temperature?

Find the measures of the angles of a triangle if they are in the ratio 2 : 3 : 4.

Factorise the quadratic expression 12ϰ² – 7ϰ + 1.

Find the least value of the function y = 3sin(ϰ + π) + 3.

How does refrigeration help stop food from going bad?

Which part of the human brain is concerned with reflexes controlling.

Which vitamin helps to maintain resistance to infectious diseases?

A metal cation forms a precipitate when H₂S is bubbled through its solution. If it takes a fairly long time for the precipitate to form, which alternative reagent will you use to get rapid results?

Which anion is mostly responsible for temporary hardness of water?

Which group of chemicals dissolved in water cannot be removed by ion-chromatography?

In bryophytes, what name is given to the structure that bears the female sex organs (Archegonia)?

In ferns, what name is given to the cluster of sporangia?

Name the pit or cavity in the archegoniophore in which the archegonia are located.

Express the following as an equation. The difference of a and b is 7.

Find the even number among the following binary numbers. A) 111, b) 101, c) 110,

Why is the acceleration of a particle that moves in a circle not zero when the particles moves with constant speed?

Which structure in plants absorbs most of the water needed by the plants?

Identify the transformation in the plane given by (ϰ, y) → (-ϰ ,y).

Find the next prime number after 173.

Find the scale of a map if a distance of 15 km is represented by 3 cm on the map.

The terminal of a solenoid are connected to those of a sensitive moving coil galvanometer. What is observed when a pole of a strong magnet is plunged into one end of the solenoid and held stationary within the solenoid?

What is the magnitude of the speed of light in vacuum to 2 s.f.

A parallel plate capacitor has capacitance 20 pF. Find the change in capacitance when the distance between the plates is decreased by 1%.

To whom do we attribute the statement; atoms of different elements may combine with each other in a fixed, simple ratios to form compound atoms

Complete the following statement, which is part of John Dalton's theory; "Atoms combine to form compounds….."

Which event occurred first: the creation of the Periodic Table by Mendeleev or the proposal of the plum pudding model by J.J Thompson

From which Latin word does the element sodium derive.

What is the 4th element in Group 2.

Name the Chemist whose name is associated with addition reactions to double bond in Organic Chemistry?

The mass of a photon is approximately 1.67 × 10^-27 kg. What is the approximate mass of a tritium nucleus?

Sand is poured vertically onto a sand heap on a horizontal surface at a rate of 0.5 kg/s. Find the average force on the surface if the sand particles fall on the heap at 6 m/s.

What accounts for the difference between the mass of an atomic nucleus and the sum of the masses of its nucleons?

Find the number of subsets of a set of 4 elements.

Find the number of proper subsets of a set of 4 elements.

Find the number of proper non-empty subsets of a set of 4 elements.

Name the taxon in which the organisms are believed to be related only by descent.

Name the taxon in which the organisms are so similar to one another.

Name the piece of glassware that must be present in a set up for heating a mixture under reflux such that the solvent is not lost as a vapour.

How many openings does a distillation head have and why?

Find the number of sides of a regular polygon if an interior angle has a measure of 170°.

If 3ϰ = 5y, find the ratio of ϰ to y.

Find the next term in the sequence 5, 1, 6, 7, 13, . . .

A very wide cistern contains water to a depth of 5 m. find the speed with which water exits a narrow pipe at the bottom of the cistern.

Two very large parallel plates 2 cm apart are maintained at a potential difference of 10 V. Find the magnitude of the electric field between them.

Which of the following is not a distance unit: astronomical unit, arc second, parsec, light year, steradian?

In which part of the stomach of ruminants are digestive juices secreted?

Which type of insect is responsible for the transmission of the groundnut rosette virus?

Which blood cells are involved in the immune response of vertebrates?

Assuming the batteries installed in mobile phones are dry cells what type of cells are they?

Name the electrolyte in lead storage cells, normally referred to as car battery.

What is the major constituent of the LPG for domestic used produced from Atuabo in the Western Region of Ghana?

The moment of inertia of a 4 kg object about an axis passing through its centre of mass is 5 kg m². Find the moment of inertia of the object about a parallel axis 0.5 m from its centre of mass.

A heat engine absorbs 2.0 kJ of thermal energy from a hot reservoir and rejects 15 kJ to a cold reservoir. Determine the thermal efficiency of the engine.

Find the magnification produced by a 20 cm focal length lens of an object 100 cm from the lens.

Given that CosA = ¼ and A is acute, find tanA.

Solve the simultaneous equations ϰ – 2y = 1, 3ϰ + y = 10.

Express the set in the set-builder notation {2, 3, 5, 7, . . . }

What name is given to plants that grow in saline water?

What name is given to plants that develops in dry conditions?

What name is given to plants that grows in sand or sandy soil?

Which organelle has variable shape and size and, morphologically, can be compared with Amoeba and white blood cells?

Which organelles in eukaryotic cells are involved in the breakdown of very long chain fatty acids and branched chain fatty acids?

If f(x) = 2x – 3, evaluate f^-1(5).

Find the number of axes of symmetry of a rhombus.

Find the length of the diagonal of a rectangle of sides lengths 8 cm and 15 cm.

Which of the two metals, magnesium and aluminium, has a lower first ionization energy?

Which of these two elements, Nitrogen and Oxygen, has a lower atomic number?

How many known elements are in Group (VII).

A tuned spring-mass system has a natural frequency of 5 Hz. What is the mass in the system if the stiffness of the spring is 8 m^-1?

What is the moment of inertia of a thin spherical shell of radius R and mass M about an axis passing through the centre of the shell?