Colour mixing

Adding white to red produces a tint. The colour family, or hue, remains red, although the mixture becomes paler; its value therefore becomes lighter. This does not turn the colour green or blue, and the hue does not disappear unless the red is completely visually overwhelmed. Hence option A correctly describes the effect of adding white.

RGB uses additive mixing: the light energy from red, green and blue combines rather than being absorbed by pigments. When all three channels are present at equal, sufficiently high intensity, their combined stimulation is perceived as white light. Black represents the absence of emitted light, while brown and orange require different combinations or lower intensities. Thus option B is correct.

Pigment mixing is subtractive because pigments absorb selected wavelengths from incoming white light; combining more pigments usually removes more light and produces a darker or less saturated result. Light mixing is additive because emitted red, green or blue light is added together, and equal strong RGB light produces white. Consequently, option A states the fundamental difference.

The governing concept is colour purity during pigment mixing. A brush carrying residue from another colour, muddy water, or contaminated paint introduces unwanted pigments and makes the intended secondary colour dull. Using a clean brush, clean water when needed, and uncontaminated primary paints keeps the mixture closer to the desired hue. Black, dirty water, and all three primaries reduce clarity, so option A is correct.

The governing concept is controlled pigment mixing. A secondary colour is normally made by combining the required pair of primaries, such as yellow plus blue for green. Adding the remaining primary introduces all three pigment families; because their combined effect tends toward neutralisation, the mixture can lose saturation and become dull or muddy. It does not create white, erase paper, or simply increase brightness, so option A is correct.

The governing concept is the difference between primary and secondary pigment colours. Mixing any two of the traditional primary colours produces a secondary colour: red plus yellow gives orange, yellow plus blue gives green, and red plus blue gives violet. Consequently, none of the listed pairings produces a primary colour, so option D is correct.

The governing concept is colour mixing by proportion. Yellow and blue combine to produce green, but the colour that is present in the larger amount determines the visible bias. Therefore, using more yellow and less blue produces a green that shifts toward yellow. Equal quantities give a more balanced green, while more blue gives a blue-dominant green. Red is not part of this two-colour mixture.

The governing concept is proportional colour mixing. Red and blue combine to make violet, and the mixture takes on a blue-dominant appearance when blue is used in the greater proportion. Thus, adding more blue while using less red makes the result shift toward blue violet. More red would create a redder violet, yellow would move the mixture toward a different colour relationship, and equal yellow and blue produces green rather than violet.

The governing concept is colour mixing and the position of related hues. Red and yellow are primary colours that combine toward orange. Because only a little red is added to yellow, the mixture will remain yellow-biased but move toward the orange family, often appearing yellow-orange. Green would require yellow and blue, violet would involve red and blue, and blue is not produced by this combination. Hence, option C is correct.

The governing concept is colour bias created by unequal proportions. Blue and yellow mix to form green. Since the amount of yellow is small and blue remains the larger component, the resulting green keeps a blue bias and appears bluish green. A reddish orange mixture would require red and yellow, yellowish red would involve red with yellow, and reddish violet would involve red and blue. Therefore, A is the only suitable shift.

The governing concept is subtractive pigment mixing. Each pigment absorbs part of the available light; combining red, yellow, and blue over substantial amounts increases broad absorption and usually produces a dull, muddy, dark neutral colour rather than a bright one. Therefore option A is correct. White is associated with additive light mixing, green needs mainly yellow and blue, and orange comes primarily from red and yellow.

The governing concept is proportion in colour mixing. Making a series with different amounts of two primary colours, such as more red and less yellow followed by equal parts, shows how the resulting hue shifts and which colour dominates. Therefore option A is correct. Black lines and uncoloured paper provide no mixing evidence, while equal amounts of all three colours do not demonstrate changing proportions and may produce a dull neutral mixture.

The governing concept is colour contamination during subtractive mixing. Clean yellow and blue normally produce green, although their ratio can change the shade. A trace of red, often left in a brush, palette, or paint container, partially neutralises green because red is opposite green on the colour wheel, making the mixture dull or muddy. Therefore option B identifies the most likely cause; options C and D mainly affect warmth or intensity, not necessarily muddiness.

The governing concept is the effect of an unwanted third primary in a secondary-colour mixture. Violet is formed from red and blue, so clean pigments and tools are needed. If yellow contaminates either colour, it combines with the mixture and reduces the clarity of violet, often making it dull or brownish. Thus option A is correct. Clean colours, a clean palette, and a suitable ratio are helpful practices, so options B, C, and D do not explain the failure.

The governing concept is complementary-colour neutralisation. Orange is the secondary colour produced by mixing red and yellow. Blue is opposite orange on the colour wheel, so even a small amount of blue can reduce orange’s saturation and shift the mixture toward brown or grey. Therefore option B is correct. Clean red and yellow, equal quantities, or a new brush do not normally create brown; contamination or dirty tools are the more plausible explanation.

The governing concept is colour mixing: primary colours serve as the basic starting colours from which many secondary and intermediate colours can be developed. The ability to combine them and observe different results demonstrates the foundation of colour creation, so option A is correct. Line concerns marks and contours, linear perspective concerns depth, and shape balance concerns visual arrangement; none of these explains the production of new colours.

The governing concept is practical demonstration of colour knowledge rather than simple recall. Mixing two primary colours in different ratios requires the learner to apply the colour system, observe how the resulting secondary colour changes in hue or intensity, and identify the results. Thus option A is the strongest test. Writing names checks memory only, drawing circles checks shape-making, and measuring a brush checks a tool property, not colour understanding.

The governing concept is colour intensity, also called saturation or chroma. Grey contains no strong hue, so mixing it with a bright primary colour generally reduces the colour’s intensity and makes it look muted or subdued. Thus option A is correct. Grey does not purify a colour, automatically turn every colour into a secondary colour, or completely remove its hue; the exact appearance depends on the proportions used.

The governing concept is subtractive pigment mixing in the traditional RYB system. When two primary pigments are combined, a new secondary colour can result: red plus yellow produces orange. Thus option C correctly describes the demonstrated property. Option A is too limited, option B contradicts the definition of primary colours, and option D is not the normal result of this pair.

Colour balance depends on the relative proportions of the pigments. Green is produced by combining blue and yellow; if the mixture contains more yellow than blue, the yellow component has greater visual influence and the green shifts toward a yellowish green. Thus option B is correct. More blue would make it bluer, while removing both colours cannot produce the stated mixture.

The governing idea is that the relative quantity of each pigment influences the colour bias of a mixture. Violet is formed from red and blue, so adding more red makes the mixture appear closer to red while it remains violet overall. Option A is therefore correct. More blue would produce bluish violet; yellowish and greenish violet are not the expected results of simply increasing red.

The governing concept is additive colour mixing, used by screens and the RGB model. Blue light and green light stimulate the eye together; their combined signal is perceived as cyan, so option A is correct. Yellow requires red plus green light. Orange and brown are not the standard results of combining equal blue and green screen light, and brown usually depends on lower brightness and surrounding colours.

This uses additive colour mixing in the RGB system. When red light and green light are emitted together at suitable intensity, the eye perceives their combined stimulation as yellow, making option B correct. Violet would require a blue component with red, blue alone is not the result of red plus green, and black represents the absence of emitted light rather than a mixture of these two active lights.

The governing concept is additive mixing of coloured light. In the RGB model, red and blue are added while green is absent; the combined visual stimulus is perceived as magenta, so option A is correct. Green comes from green light alone, yellow is produced by red plus green, and cyan is produced by green plus blue. These results apply to light, not ordinary pigment mixing.

Printing uses the subtractive CMY model, in which coloured inks remove selected wavelengths from white light. Cyan ink absorbs much of the red component, while yellow ink absorbs much of the blue component; the reflected light is therefore mainly green. Option B is correct. Magenta plus yellow produces red, cyan plus magenta produces blue, and red plus blue describes neither the standard CMY primary pair nor this printing process.